VCU Torque test results

[helijohn]

All this techno chat is very difficult to follow but I am beginning to conclude that a (FL) VCU is a PITA. I may be old fashioned but a good old transfer box is looking more and more appealing.

 

[Joe_H]

All this techno chat is very difficult to follow but I am beginning to conclude that a (FL) VCU is a PITA. I may be old fashioned but a good old transfer box is looking more and more appealing.

Naw, it's like Grumpy said a while back - it just doesn't give you AIDS.. if you treat it right and check it from time to time using the full lock forward and reverse test - or the OWUT if you can be bothered with the extra time and effort to do something that is not as informative as the lock test and takes a lot more time.

BTW, the only reason Bell use a check of the torque by hand is on a newly re-conned unit on the bench (presumably as each re-con they do will exhibit the same required turning force and is a good simple check as to the QC of the re-con process. They do not use it to test a NON re-conned unit.

 

[helijohn]

They do not use it to test a NON re-conned unit.

By that do you mean a new factory unit?

 

[Joe_H]

By that do you mean a new factory unit?

Hi John, no mate, what I mean is that afaik they wouldn't use that test at all on a unit returned for recon to assess its condition etc - it would not tell them anything really useful. They are - again imho - simply testing for repeatability of the measurement of a newly re-conned unit prior to fitting on a vehicle - just to ensure nothing has gone a miss in the re-con process. If you look at the oft' referred to you tube video it clearly says testing their newly re-conned unit.
Don't get me wrong re the OWUT, it is reasonably informative but the vehicle is static - and it takes time and effort to do. The method recommended by BELL is feeling for tightness on lock forward and reverse which takes seconds and is also a part of driving that most people do every day. Anyone can tell if they feel a slight bind - as if the brakes are binding on full lock - no effort required on the part of the driver. Any tightness would indicate an issue once brake binding had been ruled out - which is a complete no brainer really as binding does not occur ONLY on full lock and would not increase on full lock. Hence the test is simple and reliable and virtually instantaneous. you are in effect monitoring it every day as you will instinctively feel something 'different' on lock.
Joe

 

[helijohn]

Hi John, no mate, what I mean is that afaik they wouldn't use that test at all on a unit returned for recon to assess its condition. The method recommended by BELL is feeling for tightness on lock forward and reverse which takes seconds
Joe

Thanks Joe. I must admit before I bought the FL I took it on a test drive. When I pulled in to the garage forecourt I actually mentioned to the seller that the steering seemed heavy "It's as if the brakes are on" I said. This is partly what led me to believe later that there was an issue and when I did the wheel test it took mine 3 minutes to drop the 45°. I was aware of the service issues of VCUs from what I read prior to looking for FLs but I had a very limited know how then compared to my knowledge now!
I feel I dropped the ball slightly but it was cheap and it was hard to find a 3 door Kalahari diesel auto but if you asked me would I do it again the answer would probably be a resounding no.

Interestingly, when I took my VCU to Bell they did the same test to mine as the recon one that I was having at the same time - both together - so I could see the "fall" - the two were rigged up side by side (almost). They said mine was half the speed of theirs and indeed mine was falling slower but TBH I was expecting it to be 10X slower so to speak. I expected mine to not really move under weight at all frankly.

I sort of like the idea of the FL being converted to just front wheel drive but it is such a waste as I did have 4WD as a reason for getting not just this car but any car. Don't get me wrong, I like all wheel drive and saw the benefits when I had my (two) Rav4s it's just that maybe I am old school on this.

 

[Joe_H]

Thanks Joe. I must admit before I bought the FL I took it on a test drive. When I pulled in to the garage forecourt I actually mentioned to the seller that the steering seemed heavy "It's as if the brakes are on" I said. This is partly what led me to believe later that there was an issue and when I did the wheel test it took mine 3 minutes to drop the 45°. I was aware of the service issues of VCUs from what I read prior to looking for FLs but I had a very limited know how then compared to my knowledge now!
I feel I dropped the ball slightly but it was cheap and it was hard to find a 3 door Kalahari diesel auto but if you asked me would I do it again the answer would probably be a resounding no.

Interestingly, when I took my VCU to Bell they did the same test to mine as the recon one that I was having at the same time - both together - so I could see the "fall" - the two were rigged up side by side (almost). They said mine was half the speed of theirs and indeed mine was falling slower but TBH I was expecting it to be 10X slower so to speak. I expected mine to not really move under weight at all frankly.

I sort of like the idea of the FL being converted to just front wheel drive but it is such a waste as I did have 4WD as a reason for getting not just this car but any car. Don't get me wrong, I like all wheel drive and saw the benefits when I had my (two) Rav4s it's just that maybe I am old school on this.

Hi John,
The test certainly showed the comparison - and indeed is the only way they can do it off the vehicle. As I said before. I am not against the OWUT, I simply believe there are better and far simpler ways of determining the condition of your VCU. As you will have no doubt noticed with the new Bell unit, there is no feeling of any tightness at all on lock in either forward or reverse. This indicates that any noticeable tightness is a cause for concern. This is going to be noticed by the driver at any point that he is driving and makes that particular manoeuvre - which is often, hence a really great way to keep an eye on things. It is subconscious after a while - as in most things automotive you notice when something changes either feel or noise etc.
Anybody who wants to go to the hassle of the OWUT - fine - no worries - but it will tell them nothing more regarding when the unit is reaching the end of it's serviceable life. It will also tell you nothing useful really when buying a vehicle compared to the actual driving lock test. Simpler is better. It isn't really a case either of 'how much tightness' - it is any - so nothing to quantify as an actual figure is needed. I do not in any way believe that any vcu that could be judged as 'suspect' by the OWUT would not give a noticeable tightness on lock, ERGO, no point in the OWUT test for me at all when there is a FAR simpler and totally reliable test that I can perform at will and in fact do on most days, not deliberately, just simply that I often need to use full lock coming into the farm and out of it. Even if I drove a route that didn't need to use full lock I could do it at any time on any car park.
Also fully agree with AWD v 2WD - I really did not like my freeby in 2WD when I was sorting the IRD out (bought with a failed IRD and no prop / vcu etc - I knew what I was buying )
Having such a vehicle in 2WD is sacrilidge to me lol....
Joe

 

[GrumpyGel]

Hi Grumpy - I am quite surprised that you think the article is 'brilliant' and a 'good find' as you have quoted the misleading graphs and info from there before

That site - firstly - is a re conditioner of vcu units. (note the PUCH service sticker he stuck on the home built vcu turning unit - purely for effect - nothing to do with PUCH!)
Also, most of the stuff he writes is 'selectively' plagiarised from the original (and early) work of Wolfgang Peschke, (ie - made to fit his beliefs and sell his products)

If you want to refer to the article that he plagiarised then look at the link to Peschke's original papers referred to on the linked site - which also includes a graph and data by VW. showing the generalised torque transfer characteristics.(note - not the minute drop in torque transfer as shear load increases - which does NOT mean that the torque to the rear DECREASES with increases slippage - the effect of the torque increase from the delta of the shear balances the slight viscosity drop of the fluid (which is non Newtonian). The rate of torque transfer - in actual use remains more or less linear until hump mode is achieved.
The technical publication by Peschke and the data from VW are far more reliable than a guy who wants to make his re-con units fit 'his' model.

http://syncro.org/the-viscous-coupler/

Peschke's original work

http://www.syncro.org/sitephotos/Galleries/peschke_viscous_coupling_article/pages/VC1_jpg.htm

Hi Joe - You should think before you post

You say I have quoted that page before, well it must have been in a previous life, because I've never seen it before, nore a lot of the info it discusses.

That page does not plagiarise anything, it clearly states that it is taking and collating information from other sources.

I'm fully aware of the document you linked to. It was put together by Peschke at VW for the Society of Automotive Engineers at a time when probably most development, testing and analysis was being performed with viscous couplings. It contains a lots of science, fact and yes interpretation. You belittle it by saying it is "made to fit his beliefs and sell his products" then go on to use info from it to boost your perspective. So what is it, decent scientific analysis or crap?

There are 14 graphs in the document, which one are you picking?

So are you saying that the Silicon oils used in VCUs are dilatant? Are you saying that they are shear thickening Non-Newtonian? That is how people percieve the operation of a VCU "should" be, but it is NOT. You need to stop relying on WIKI for your info, from 2 weeks ago...

One of the best explanations is the generalised wiki article. Also the term 'dilatant fluid' (appertaining to the non -newtonian behaviour)
https://en.wikipedia.org/wiki/Viscous_coupling_unit

Joe:

It is why I said "Confirms (again!) that the silicon fluid is not dilatant and the rate of torque transfer in viscous mode diminishes as shear increases.".

Can you please explain how from that line you interpret it as "that the torque to the rear DECREASES with increases slippage"? Read again my friend.

Anyway, that line was all I wrote about the SAE doc info - and has been discussed to death. All the other info regarding wear and lower viscosity, and how that applies to Freelander, has not been discussed greatly which is why I think its a great find. It is not information taken from SAE document.

 

[Joe_H]

Hello Grumpy - got out of the wrong side ?
I was referring to the graph you posted - https://www.landyzone.co.uk/land-rover/rear-wheel-bounces-in-tight-turns.300391/page-2 (post 40) which I mistakenly believed was from that specific site we are discussing - It appears not (apologies)- it appears he simply just copied that as well - and tidied it up a bit...

I'm fully aware of the document you linked to. It was put together by Peschke at VW for the Society of Automotive Engineers at a time when probably most development, testing and analysis was being performed with viscous couplings. It contains a lots of science, fact and yes interpretation.

Interesting interpretation Grumpy mate - if you check the date of publication of the document it was a year AFTER the VW Synchro was introduced. - so slightly more than speculation.. ! - so, maybe 'think before you post lol .

You belittle it by saying it is "made to fit his beliefs and sell his products" then go on to use info from it to boost your perspective. So what is it, decent scientific analysis or crap?

I am not belittling the Peschke document at all. I believe it is the foundation for all the most respected views on VCU operation - written by a top guy at VW - who were actually using the unit or well into the testing phases as the document lists data up to 1985 .

I do not believe the page you linked to is scientific analysis in any way though.

So are you saying that the Silicon oils used in VCUs are dilatant? Are you saying that they are shear thickening Non-Newtonian? That is how people percieve the operation of a VCU "should" be, but it is NOT. You need to stop relying on WIKI for your info, from 2 weeks ago...

I am saying that with information gleaned the fluid is definitely non Newtonian. The 'shear thinning' is a most over used description and you read far too much into it. The viscosity actually is constant throughout most if not all of the range of viscous mode if you go from the data that I believe you quoted from the suppliers data sheet for viscous oils. It only drops off at a high shear rate which the vcu is unlikely to enter before hump mode. - if you want to decode the s-1 in terms of rpm etc then feel free.
If you look back to that post from a few weeks ago, there was also a good discussion between us about the 'degressive' nature and it's supposed meaning.

Can you please explain how from that line you interpret it as "that the torque to the rear DECREASES with increases slippage"? Read again my friend.

I did not say what you wrote there Grumpy, I said "which does NOT mean that the torque to the rear DECREASES with increases slippage" (should have read increase(d) not increases - but that is by the by) - I also qualify that as - the effect of the torque increase from the delta of the shear balances the slight viscosity drop of the fluid (which is non Newtonian). The rate of torque transfer - in actual use remains more or less linear until hump mode is achieved.

As, in the event of slippage and shear, if the slippage remains constant (unlikely except on a test rig) the temp increases rapidly and the hump mode is entered. Also, if slippage increases then even if some shear thinning occurred, the increased slippage causes an even more rapid rise in temp and hump mode lock up.
Ask Tony - if - when performing his superb test on the VCU with the scales and bar in viscous mode (I certainly presume it wasn't in hump mode) if he noticed this theoretical decrease in torque ?

We can keep going around in circles on this but it is pointless you will only catch AIDS or split a condom
Joe

 

[GrumpyGel]

Hello Grumpy - got out of the wrong side ?
I was referring to the graph you posted - https://www.landyzone.co.uk/land-rover/rear-wheel-bounces-in-tight-turns.300391/page-2 (post 40) which I mistakenly believed was from that specific site we are discussing - It appears not (apologies)- it appears he simply just copied that as well - and tidied it up a bit...


Interesting interpretation Grumpy mate - if you check the date of publication of the document it was a year AFTER the VW Synchro was introduced. - so slightly more than speculation.. ! - so, maybe 'think before you post lol .




I am not belittling the Peschke document at all. I believe it is the foundation for all the most respected views on VCU operation - written by a top guy at VW - who were actually using the unit or well into the testing phases as the document lists data up to 1985 .

I do not believe the page you linked to is scientific analysis in any way though.



I am saying that with information gleaned the fluid is definitely non Newtonian. The 'shear thinning' is a most over used description and you read far too much into it. The viscosity actually is constant throughout most if not all of the range of viscous mode if you go from the data that I believe you quoted from the suppliers data sheet for viscous oils. It only drops off at a high shear rate which the vcu is unlikely to enter before hump mode. - if you want to decode the s-1 in terms of rpm etc then feel free.
If you look back to that post from a few weeks ago, there was also a good discussion between us about the 'degressive' nature and it's supposed meaning.


I did not say what you wrote there Grumpy, I said "which does NOT mean that the torque to the rear DECREASES with increases slippage" (should have read increase(d) not increases - but that is by the by) - I also qualify that as - the effect of the torque increase from the delta of the shear balances the slight viscosity drop of the fluid (which is non Newtonian). The rate of torque transfer - in actual use remains more or less linear until hump mode is achieved.

As, in the event of slippage and shear, if the slippage remains constant (unlikely except on a test rig) the temp increases rapidly and the hump mode is entered. Also, if slippage increases then even if some shear thinning occurred, the increased slippage causes an even more rapid rise in temp and hump mode lock up.
Ask Tony - if - when performing his superb test on the VCU with the scales and bar in viscous mode (I certainly presume it wasn't in hump mode) if he noticed this theoretical decrease in torque ?

We can keep going around in circles on this but it is pointless you will only catch AIDS or split a condom
Joe

The Syncro was not the only vehicle other than Freelander to use VCUs.
What page have I linked to?
I didn't ask you to explain decreased transfer with increased slippage - I asked you how you interpreted what I said. I asked you to read again, and I ask again, that you read what I said.

I write 1 line about how the VCU works and this **** happens. I write a couple of paras about new stuff on wear, which is of far more importance to us, and why the link from Tony IMHO was a great find, and no discussion !

 

[Joe_H]

The Syncro was not the only vehicle other than Freelander to use VCUs.
What page have I linked to?
I didn't ask you to explain decreased transfer with increased slippage - I asked you how you interpreted what I said. I asked you to read again, and I ask again, that you read what I said.

I write 1 line about how the VCU works and this **** happens. I write a couple of paras about new stuff on wear, which is of far more importance to us, and why the link from Tony IMHO was a great find, and no discussion !

Hi GG,
Ref page you linked to - if that is what you mean ? Post 48 -- dow corning - https://www.landyzone.co.uk/land-rover/rear-wheel-bounces-in-tight-turns.300391/page-3#post-3753339

I have no idea what part or comment or statement or ''what line' you 'think' that I was 'interpreting' in my remark re torque transfer - it was not in response to any specific 'line' or remark or comment you made.
regarding 'wear'
I do not believe that 'wear' is an issue that we need to be concerned about - presuming you are referring to the destructive tests done by Puch on some early unit.
I have never personally heard of any issues at all regarding wear in the plates of freelander vcus - Perhaps Austin at Bell's or someone who literally sees hundreds of the things cut apart would know better. It is not something he mentions - (IMO) It would be in the information he publishes regarding the VCU failures if that was happening.
The same is true of the bearings within a VCU - the VCU has to have both bearings and extreme pressure seals, yet we hear nothing of issues with those either.
Perhaps there are thousands of freelanders driving around with worn plates that never enter hump mode ? /// however, even that would have been picked up by the re-conditioners one would presume as a heck of a lot of stock is bought from breakers yards. Again, it would be in the interest of the reconditioners to point out such an issue if it was occurring as a major reason and method that the vcu could fail and hence a need to change it.
We have the knowledge now to know when a VCU is reaching the end of it's service life and avoid the costly failed transmissions of the past/ Also the knowledge regarding tyre sizes and their importance in keeping the mechanical parts in the same box. .

 

[GrumpyGel]

Hi GG,
Ref page you linked to - if that is what you mean ? Post 48 -- dow corning - https://www.landyzone.co.uk/land-rover/rear-wheel-bounces-in-tight-turns.300391/page-3#post-3753339

I have no idea what part or comment or statement or ''what line' you 'think' that I was 'interpreting' in my remark re torque transfer - it was not in response to any specific 'line' or remark or comment you made.
regarding 'wear'
I do not believe that 'wear' is an issue that we need to be concerned about - presuming you are referring to the destructive tests done by Puch on some early unit.
I have never personally heard of any issues at all regarding wear in the plates of freelander vcus - Perhaps Austin at Bell's or someone who literally sees hundreds of the things cut apart would know better. It is not something he mentions - (IMO) It would be in the information he publishes regarding the VCU failures if that was happening.
The same is true of the bearings within a VCU - the VCU has to have both bearings and extreme pressure seals, yet we hear nothing of issues with those either.
Perhaps there are thousands of freelanders driving around with worn plates that never enter hump mode ? /// however, even that would have been picked up by the re-conditioners one would presume as a heck of a lot of stock is bought from breakers yards. Again, it would be in the interest of the reconditioners to point out such an issue if it was occurring as a major reason and method that the vcu could fail and hence a need to change it.
We have the knowledge now to know when a VCU is reaching the end of it's service life and avoid the costly failed transmissions of the past/ Also the knowledge regarding tyre sizes and their importance in keeping the mechanical parts in the same box. .

 

[GrumpyGel]

Hi GG,
Ref page you linked to - if that is what you mean ? Post 48 -- dow corning - https://www.landyzone.co.uk/land-rover/rear-wheel-bounces-in-tight-turns.300391/page-3#post-3753339

I have no idea what part or comment or statement or ''what line' you 'think' that I was 'interpreting' in my remark re torque transfer - it was not in response to any specific 'line' or remark or comment you made.
regarding 'wear'
I do not believe that 'wear' is an issue that we need to be concerned about - presuming you are referring to the destructive tests done by Puch on some early unit.
I have never personally heard of any issues at all regarding wear in the plates of freelander vcus - Perhaps Austin at Bell's or someone who literally sees hundreds of the things cut apart would know better. It is not something he mentions - (IMO) It would be in the information he publishes regarding the VCU failures if that was happening.
The same is true of the bearings within a VCU - the VCU has to have both bearings and extreme pressure seals, yet we hear nothing of issues with those either.
Perhaps there are thousands of freelanders driving around with worn plates that never enter hump mode ? /// however, even that would have been picked up by the re-conditioners one would presume as a heck of a lot of stock is bought from breakers yards. Again, it would be in the interest of the reconditioners to point out such an issue if it was occurring as a major reason and method that the vcu could fail and hence a need to change it.
We have the knowledge now to know when a VCU is reaching the end of it's service life and avoid the costly failed transmissions of the past/ Also the knowledge regarding tyre sizes and their importance in keeping the mechanical parts in the same box. .

Dunno what happened there!

All of the tests we talk about on the VCU only test the viscous mode, not hump mode, but you are quite right - I don't think anyone has posted on here that their VCU has exploded because it couldn't sustain hump mode!

Maybe the info in that post is just academic, but I find it interesting none-the-less.

Maybe in Freelander setup the fluid will degrade faster than the plates and blow other parts in the transmission before the VCU itself.

I feel sure I have seen a post or 2 where fluid has escaped from VCUs. In what context I do not remember. Maybe it was poor seals, and overfilled recon - but maybe it was due to worn plates allowing the temp to rise too far and pushing fluid out. Knowing how the plates wear might help if there are future reports of that.

 

[Joe_H]

Dunno what happened there!

All of the tests we talk about on the VCU only test the viscous mode, not hump mode, but you are quite right - I don't think anyone has posted on here that their VCU has exploded because it couldn't sustain hump mode!

Maybe the info in that post is just academic, but I find it interesting none-the-less.

Maybe in Freelander setup the fluid will degrade faster than the plates and blow other parts in the transmission before the VCU itself.

I feel sure I have seen a post or 2 where fluid has escaped from VCUs. In what context I do not remember. Maybe it was poor seals, and overfilled recon - but maybe it was due to worn plates allowing the temp to rise too far and pushing fluid out. Knowing how the plates wear might help if there are future reports of that.

Hi GG, I also actually find some of the info there quite interesting, especially the info regarding the troubles with the early units in respect of strength and seals.I find it quite amazing - well - literally amazing - to think that they had an oil back flow INTO the vcu when a negative pressure was applied due to temperature drop - not a huge one either. They must have used very very unidirectional pressure seals. (I believe MOST HP seals are indeed almost totally unidirectional - but not utterly.) . The good thing about SDP (Puch) is that they made most of the mistakes on the early units .

Who knows really how many VCU failures (premature hump due to fluid degradation) - which then caused transmission problems were actually caused by tyre issues ? - and not directly by a VCU failure due to simply MTBF or just wearing out in normal use. I would hazard a guess it is probably more down to tyres. Even when the lessons have been learnt - for those of us here on these forums at least - about the HUGE importance of tyres and pressures, it is so difficult if not impossible to determine the excess loads already placed on transmission components by tyre issues in the past (most vehicles by now have had multiple owners and whatever service history is there tells little as to tyre pressures and wear. Many vehicles theoretically could be already severely stressed in vital areas and not take much to actually cause failures.We can say with absolute certainty that the tyre maintenance regime is absolutely critical to the transmission integrity, What we cannot really say is that if the tyres were always maintained as they should be regarding sizing and pressures, what the actual life of a vcu would be ?.
Again though, we DO know, and can test for, the warning signs of VCU issues and we DO know what not to do with tyres. That is something that is invaluable to ALL owners. The 'problem' - is - imho - that so many vehicles are 'living on the edge' due to past issues that may not have actually caused noticeable damage but HAS caused hidden damage. I suppose a good analogy is an aircraft with metal fatigue... our tyre issues are an analog of the Comet's 'square windows' - When the damage has been done but has not yet manifested as a failure it is often only a slight push needed to put it over the edge.
The good thing though is that in the event of suspected stresses placed, the IRD should not be a magical box that the reasonably competent owner could not check over by partially stripping and examining. It takes far longer to R&R the IRD than to strip and inspect it - it can be done in less than an hour and is in nice easy to manage simple lumps. There is hope for the future lol

 

[GrumpyGel]

Yes, you would think it rookie mistake from the designers to allow the oils/fluids to to exchange so predictably!

I know you are a strong proponent of the turn on lock tests - but reading up on the Syncro their units appear to make the Freelander's a marvel of reliability! I was just reading how after a long motorway drive in a Syncro, you'd turn off into a petrol station and the VCU would do the braking for you!

As you say, you really have no idea when you buy what condition the IRD (and diff) are in. It makes buying a cheap 2WD a lot more attractive than a high priced supposed FSH well maintained car. At least you know exactly how much you have to spend to get it to be a car with a good transmission.

When I took the IRD off the L Series, it came off just like mechano really - just undo the bolts - admittedly a lot of bolts and some very tight awkward to get at bolts - but yes relatively straight forward. My problems started when I tried to split it. I had all the bolts undone but I couldn't get the damm thing to split open. Frustrated, I just left it for a while. Thankfully I left it in full sunshine because when I returned to it, it was in 2 pieces

The thing that amazed me most, was that after I put it all back together again, the car worked I was convinced for the first few days that it was just going to fall to bits or something - but it never did and has been running well now for 3 years!

 

[Joe_H]

Yes, you would think it rookie mistake from the designers to allow the oils/fluids to to exchange so predictably!

I know you are a strong proponent of the turn on lock tests - but reading up on the Syncro their units appear to make the Freelander's a marvel of reliability! I was just reading how after a long motorway drive in a Syncro, you'd turn off into a petrol station and the VCU would do the braking for you!

As you say, you really have no idea when you buy what condition the IRD (and diff) are in. It makes buying a cheap 2WD a lot more attractive than a high priced supposed FSH well maintained car. At least you know exactly how much you have to spend to get it to be a car with a good transmission.

When I took the IRD off the L Series, it came off just like mechano really - just undo the bolts - admittedly a lot of bolts and some very tight awkward to get at bolts - but yes relatively straight forward. My problems started when I tried to split it. I had all the bolts undone but I couldn't get the damm thing to split open. Frustrated, I just left it for a while. Thankfully I left it in full sunshine because when I returned to it, it was in 2 pieces

The thing that amazed me most, was that after I put it all back together again, the car worked I was convinced for the first few days that it was just going to fall to bits or something - but it never did and has been running well now for 3 years!

LOL - I ALWAYS feel that something is going to drop off or fail in a catastrophic way after a repair - (Never on other people though )
What did you actually do to your IRD ? is that the one that went 2WD, or was this a rebuild ?.
I deliberately looked for a mint condition freelander - body interior underside etc with 2WD and a lower price - knowing that the IRD was going to be captain cooked and probably the diff too. That was opposed to paying far more for a fully 4WD unit that I had no knowledge of the previous stresses applied on the transmission. I knew it was going to be an L series because a. they are simply the best and b. that is all we have here !.. I still find it amazing, I have never seen a 1.8 or TD4 here (there must surely be /some/ - but a mate that runs a local place 'freelander solutions' (in Portuguese) is inundated with work from all over the north of Portugal and ALL he gets are L series ... not engine work lol... well - to be honest - he has replaced quite a few engines I must confess - but that is due to leaking blocks. The are some weak areas on the casting of the block (like bubbles) - at the back of the motor - . This is not an issue normally but the tight buggers here think that antifreeze is a waste of money because it never freezes ! - hence years and years of no corrosion inhibitor - that FINDS the weak spots..... Any - I digress ... yes, so by getting a unit with 2WD (Props off) even though it drove well apart from the 1700-2200 rpm shudder (clutch judder due to oil seepage from crank rear bearing -common issue - now fixed) I knew the IRD would be captain cooked. Budgeting for a full recon of my unit meant I saved money on the purchase, rebuilt the unit with a few parts from my LR mate and several bearings and shims for the diff, AND bought another really mint S/H unit from the UK and a Fuel Pump for spares - for less than the price of a re-con IRD.
I cannot imagine how I would feel if I drove into the petrol station and the hippo applied the brakes via the VCU !!! - I would be under it and the prop off immediately.. no wonder the synchros had so many issues Probably loaded down like beggary at the rear with masses of gear (along with the engine etc) and a light front end. Tyres at the rear looking like a far ar$e on a stool.....

Regarding oil mixing and transfer, I am sure there must be some instances of this on the hippo in the area of gearbox to ird. The seals are pretty simple but are easily damaged by careless handling especially by some of the dodgy ird -recon - places.. there is a vid on you tube of some breakers in the UK promoting their 'ird recon' 'service' - it is frightening - they show some knuckle dragger pulling the concentric shafts out, and then dumping them back in - guaranteed to beggar the seals !... if you havent seen it I will dig it up..
One of the Subaru 4 wd (Justy ?) uses a VCU on the rear diff that is electromagnetically coupled. - same principle as an air con EM clutch. They are a neat little unit. (Still a 'normal' vcu - just that the 'in or out' of transmission is controlled by the EM clutch.)
Not supposed to be 'user serviceable' but seem to fail on the outer bearings inside a casing cover - replace as one unit - but of course it can and is reasonably easy to change the bearings - quite expansive as they are rather special units - as are the seals, but nothing compared to a new unit !. I think I prefer the always available mode though as on our hippos.
Went for a drive around the farm today as they just cleared a lot of the tracks of overgrowth for the grape harvest - great for me to play on with the superbly working bell vcu (night and day from that crappy Portuguese one!) - (and the new Avon Ranger AT boots) - but alas not enough grapes to harvest this year as it has been two hot ! Hottest since 1932. !. two weeks ago it was 40C in the shade, now with the equinox (it is like turning a switch here) - it suddenly drops to 23 / 25 and we are sat with leggings and jumpers lol.
Still waiting for the td4 servo !!! they forgot to post it last time so am awaiting the next delivery (and cannot do the remap without boosting the brakes - catch 22) - along with a new ABS mod - (did you see the pics I posted of the Wabco unit I got man ? - yike and Jeeez - what a mess !.. I am now able to strip a wabco modulator to get to all major components - I have something to practice on lol - tis beggar all use for anything else.. at least I can remove the motor and HP valves to replace the motor bearing on the eccentric cam that drives the HP pistons - common reason for 'sticky motor' errors in ABS ECU. Can also change shuttle valve switches. Quite a simple unit really.
Anyway, late here now so have a great day. If you aint seen those pics of the wabco you are in for a treat...

 

[helijohn]

I cannot imagine how I would feel if I drove into the petrol station and the hippo applied the brakes via the VCU !!! -

And that is my point!!

One of the Subaru 4 wd (Justy ?) uses a VCU on the rear diff that is electromagnetically coupled. - same principle as an air con EM clutch. They are a neat little unit. (Still a 'normal' vcu - just that the 'in or out' of transmission is controlled by the EM clutch.)

Sounds like heaven.

 

[GrumpyGel]

LOL - I ALWAYS feel that something is going to drop off or fail in a catastrophic way after a repair - (Never on other people though )
What did you actually do to your IRD ? is that the one that went 2WD, or was this a rebuild ?.
I deliberately looked for a mint condition freelander - body interior underside etc with 2WD and a lower price - knowing that the IRD was going to be captain cooked and probably the diff too. That was opposed to paying far more for a fully 4WD unit that I had no knowledge of the previous stresses applied on the transmission. I knew it was going to be an L series because a. they are simply the best and b. that is all we have here !.. I still find it amazing, I have never seen a 1.8 or TD4 here (there must surely be /some/ - but a mate that runs a local place 'freelander solutions' (in Portuguese) is inundated with work from all over the north of Portugal and ALL he gets are L series ... not engine work lol... well - to be honest - he has replaced quite a few engines I must confess - but that is due to leaking blocks. The are some weak areas on the casting of the block (like bubbles) - at the back of the motor - . This is not an issue normally but the tight buggers here think that antifreeze is a waste of money because it never freezes ! - hence years and years of no corrosion inhibitor - that FINDS the weak spots..... Any - I digress ... yes, so by getting a unit with 2WD (Props off) even though it drove well apart from the 1700-2200 rpm shudder (clutch judder due to oil seepage from crank rear bearing -common issue - now fixed) I knew the IRD would be captain cooked. Budgeting for a full recon of my unit meant I saved money on the purchase, rebuilt the unit with a few parts from my LR mate and several bearings and shims for the diff, AND bought another really mint S/H unit from the UK and a Fuel Pump for spares - for less than the price of a re-con IRD.
I cannot imagine how I would feel if I drove into the petrol station and the hippo applied the brakes via the VCU !!! - I would be under it and the prop off immediately.. no wonder the synchros had so many issues Probably loaded down like beggary at the rear with masses of gear (along with the engine etc) and a light front end. Tyres at the rear looking like a far ar$e on a stool.....

Regarding oil mixing and transfer, I am sure there must be some instances of this on the hippo in the area of gearbox to ird. The seals are pretty simple but are easily damaged by careless handling especially by some of the dodgy ird -recon - places.. there is a vid on you tube of some breakers in the UK promoting their 'ird recon' 'service' - it is frightening - they show some knuckle dragger pulling the concentric shafts out, and then dumping them back in - guaranteed to beggar the seals !... if you havent seen it I will dig it up..
One of the Subaru 4 wd (Justy ?) uses a VCU on the rear diff that is electromagnetically coupled. - same principle as an air con EM clutch. They are a neat little unit. (Still a 'normal' vcu - just that the 'in or out' of transmission is controlled by the EM clutch.)
Not supposed to be 'user serviceable' but seem to fail on the outer bearings inside a casing cover - replace as one unit - but of course it can and is reasonably easy to change the bearings - quite expansive as they are rather special units - as are the seals, but nothing compared to a new unit !. I think I prefer the always available mode though as on our hippos.
Went for a drive around the farm today as they just cleared a lot of the tracks of overgrowth for the grape harvest - great for me to play on with the superbly working bell vcu (night and day from that crappy Portuguese one!) - (and the new Avon Ranger AT boots) - but alas not enough grapes to harvest this year as it has been two hot ! Hottest since 1932. !. two weeks ago it was 40C in the shade, now with the equinox (it is like turning a switch here) - it suddenly drops to 23 / 25 and we are sat with leggings and jumpers lol.
Still waiting for the td4 servo !!! they forgot to post it last time so am awaiting the next delivery (and cannot do the remap without boosting the brakes - catch 22) - along with a new ABS mod - (did you see the pics I posted of the Wabco unit I got man ? - yike and Jeeez - what a mess !.. I am now able to strip a wabco modulator to get to all major components - I have something to practice on lol - tis beggar all use for anything else.. at least I can remove the motor and HP valves to replace the motor bearing on the eccentric cam that drives the HP pistons - common reason for 'sticky motor' errors in ABS ECU. Can also change shuttle valve switches. Quite a simple unit really.
Anyway, late here now so have a great day. If you aint seen those pics of the wabco you are in for a treat...

My IRD went after driving long distances over a couple of days on, what I'm sure was, an under inflated tyre. We had friends from the UK staying with us
for a few days, so took a couple of trips up to Arthurs Pass and Akaroa - about 500km over 2 days. As soon as we set off from home I thought the car felt a bit "different", but they were only with us for a few days, so thought I'd investigate after they left. Anyway coming back from Akaroa, under 2km from home it developed a rattle that I thought was the exhaust fallen off its carrier and then 300m from home it went BANG.

The pinion gears were shagged together with bearings etc - as I then found out, typical IRD failure. The only IRDs & VCUs I could find in NZ were going to cost $7,500 - about £3K at the time - and more than we paid for the car. I wanted it back on the road - but not at those sorts of prices and I also was completely p***sed off that it had happened and didn't want it happening again.

I considered a blanking plate, but wasn't sure the 2WD aspects of the IRD were in good enough condition. Also, if you remove the props, there's a good chance it won't get a WOF (MOT) and will need certification (more costs). So looked at the options and bought a bearing/seals/oil cooler kit from the UK. To put it back 4WD I would also need the crown/pinion gears and VCU - both expensive and heavy for shipping and would result in it being 4WD with the possibility of the same problems happening again. So I had the rebuild kit fitted and removed the gear on the pinion. Put it all back together with original props/VCU and support bearings.

Although I want my 4WD back, I can't say it was the wrong decision to go 2WD. Its done a lot of Ks taking us and other visitors where ever we've wanted to go with complete reliability. I say where ever, but of course it hasn't! It hasn't taken me on the beach, or up ski fields and although I still take it down the river bed, I probably shouldn't and I'm a lot more careful - the TC cuts in very frequently!

I have a good IRD now and a 2nd VCU to recon. I haven't really examined the rear diff since all this happened, and if I put 4WD transmission through it, I don't know if it will hold up - but I have a decent spare one of those as well. It may also need new support bearings and diff mounts if its put back to 4WD as well.

Funny you mention about the Justy. My boss's daughter rolled a Justy on the Danseys Pass Road down in Otago. It may have decent traction, but I think because its so short, its directional stability on gravel etc is pretty poor. The Justy is different to most Subarus in having a transverse engine - which is probably why it has a separate VCU. Most of them run front to back with their flat 'boxer' lumps. These have the limited slip viscous coupling center diff (as well as the front diff) inside the gearbox. These to can have the VCU disabled via an electronic clutch. There is no human control over this and I think the ECU has it turned on basically all the time apart from at start up. But most Legacies etc of a certain age will have the fuse removed!

 

[helijohn]

My IRD went after driving long distances over a couple of days on, what I'm sure was, an under inflated tyre. Although I want my 4WD back, I can't say it was the wrong decision to go 2WD. Its done a lot of Ks taking us and other visitors where ever we've wanted to go with complete reliability.

These are my very concerns with the Freelander. Just like the Suzuki Jimny had an Achilles heel (kingpin bearings which have no protection from water ingress - so wade not in one!) so I think this is the FL's Achilles heel.
Personally I think it is a great car in many respects and would better for being 2WD given the limitations that creates for the mudplugger fraternity.
I had a Rav4 which just after I bought it went bang a few times. I later found out (after unwittingly driving it home for a 100+ miles from buying it) that the tyres on the back were a different size from the front and I am sure it led to the front driveshafts failing.
Talking of Achilles heels............I had a shogun Pinin and its weakness, or one of them cos there were many, was rust; many of them if not most are rot boxes. In principle it was a superb motor. Shame really because without the rot problem I would have stuck with that car except for the engine problems it had.............actually the list was endless on it so in truth I would not have stuck with it . As a result unfortunately I get very nervous about motors that have endless faults. My Jeep Cherokee had only one fault..............lethal in snow and ice.
In case you are wondering..............................apart from my Pajero what I would recommend is Suzuki Vitara. I have had superb service from the ones I have had and have had a few!!

 

[GrumpyGel]

These are my very concerns with the Freelander. Just like the Suzuki Jimny had an Achilles heel (kingpin bearings which have no protection from water ingress - so wade not in one!) so I think this is the FL's Achilles heel.
Personally I think it is a great car in many respects and would better for being 2WD given the limitations that creates for the mudplugger fraternity.
I had a Rav4 which just after I bought it went bang a few times. I later found out (after unwittingly driving it home for a 100+ miles from buying it) that the tyres on the back were a different size from the front and I am sure it led to the front driveshafts failing.
Talking of Achilles heels............I had a shogun Pinin and its weakness, or one of them cos there were many, was rust; many of them if not most are rot boxes. In principle it was a superb motor. Shame really because without the rot problem I would have stuck with that car except for the engine problems it had.............actually the list was endless on it so in truth I would not have stuck with it . As a result unfortunately I get very nervous about motors that have endless faults. My Jeep Cherokee had only one fault..............lethal in snow and ice.
In case you are wondering..............................apart from my Pajero what I would recommend is Suzuki Vitara. I have had superb service from the ones I have had and have had a few!!

Knowing what I know now about how it works, I would probably have put it back to 4WD. However, knowing what I know now, it would also probably never have happened in the first place

I suppose it must be considered Freelander's Achilles Heel due to the frequency and impact of excessive transmission wind up - but the problem is in education/knowledge as much as/more than technical/mechanical.

 

[Alibro]

Knowing what I know now about how it works, I would probably have put it back to 4WD. However, knowing what I know now, it would also probably never have happened in the first place

I suppose it must be considered Freelander's Achilles Heel due to the frequency and impact of excessive transmission wind up - but the problem is in education/knowledge as much as/more than technical/mechanical.

Unless of course you were stupid enough to buy a K series (like I did, twice). Then it's just the other Achilles heal.