Tyre rotation

let me think a little bit...
Freelander transmission uses a viscus coupling unit to put power in the rear wheels.
to have power is needed an certain amount of difference in the rotation speed between the" front" and the "rear" shaft.
with 4 equal tires LR as set this speed difference. Front shaft rotating faster then the rear.
If we put smaller tires in the rear, the rear shaft will rotate faster giving less difference in the rotation speed and less power to the rear wheels, but putting all the transmission in less stress.
if we put smaller tires in the front, is the other way.
So, as far as i can see, the solution is to keep all the tires equal, or at least put new tires in the FRONT.... SURPRISE !!!!

@ Paulo Santos

pleeeez ..do yourself a favour ..
don't put smaller tyres on the rear

and ..

at least put new tires in the FRONT

Click to expand...

that's a no no as well

or else you'll be back here soon
asking why has your IRD exploded and the rear diff be in pieces

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Paulo Santos said:

let me think a little bit...
Freelander transmission uses a viscus coupling unit to put power in the rear wheels.
to have power is needed an certain amount of difference in the rotation speed between the" front" and the "rear" shaft.
with 4 equal tires LR as set this speed difference. Front shaft rotating faster then the rear.
If we put smaller tires in the rear, the rear shaft will rotate faster giving less difference in the rotation speed and less power to the rear wheels, but putting all the transmission in less stress.
if we put smaller tires in the front, is the other way.
So, as far as i can see, the solution is to keep all the tires equal, or at least put new tires in the FRONT.... SURPRISE !!!!

Click to expand...

No this is completely wrong. The front prop shaft doesn't turn faster than the rear as the rear gearing is set to turn the rear prop shaft 0.8% faster than the front. This means the VCU has to slip constantly with all tyres the same size. If the front tyres are larger in diameter than the rears, the this slip 0.8% ratio is increased. This increase causes the VCU to start transferring torque and damage the IRD or diff.
So please don't post advice that will cause expensive damage to someone's vehicle, should they follow it.

If the front shaft turns slower then the rear, how does it transfer power to the rear wheels ?
it is a viscous coupling unit. To transfer power it needs to slip. The faster rotating side will send power to the slower side.
Do you mean that with all tires the same size,there is a power transfer from rear wheels to the front ?

Paulo Santos said:

If the front shaft turns slower then the rear, how does it transfer power to the rear wheels ?

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It only starts to transfer torque to the rear wheels when the front wheels start to slip. The slipping front wheels then allow the front prop to spin faster than the rear, so the VCU starts to transfer drive.

Paulo Santos said:

it is a viscous coupling unit. To transfer power it needs to slip. The faster rotating side will send power to the slower side.
Do you mean that with all tires the same size,there is a power transfer from rear wheels to the front ?

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Yes but because the slip is so small, the torque transfer is small. This is why it's so important to keep the correct tyres fitted at all times. Fit a different size tyre and the VCU starts passing torque to where it's not needed, overloading the drive train.

Nodge68 is totally correct, check out this link below, I went by this when I was about to change my Freelander tyres and noticed there was a lot of disagreement as to what should be done.

http://www.freelanderspecialist.com...res-and-how-a-viscous-coupling-vcu-unit-fails

@Paulo Santos, please do not put new tyres on the front. I and others have been on here long enough to have heard and had to break the bad news to people that their drive train is knackered due to tyre installers putting new tyres on the front.
On this point you are advised to listen to those of us who have owned freelanders for a long time, I've had mine 13 years and would never put new tyres on the front.
I wouldn't even put new ones on the rear! But that's just my opinion.
Always replace a full set, I have and I'm upto 133,000 miles on my original vcu.
Mike

Paulo Santos said:

If the front shaft turns slower then the rear, how does it transfer power to the rear wheels ?
it is a viscous coupling unit. To transfer power it needs to slip. The faster rotating side will send power to the slower side.
Do you mean that with all tires the same size,there is a power transfer from rear wheels to the front ?

Click to expand...

Paulo my friend, the viscous coupling (Viscoso) is biased toward the front wheel drive via a difference in final drive ratios of around 0.8 percent (apart from the V6)
The Viscoso also allows a small amount of slip as normal. - also the viscoso is biased to operate in one direction (imho) - hence - as even described in the operators manual - the larger tyres should always be on the rear ! - when slip occurs - the gearing between the front and rear (already biased toward the front) allows the viscoso (Portuguese) to lock - however, it need to quickly be unable to 'unlock' - this is the one way bias ! - as soon as the wheel spin - or differential between front and rear stabilises it allow (because of the gearing bias) the Viscoso to 'release'. Without this bias in gearing, the viscoso would always be trying to engage hence causing transmission wind up. The viscoso (imho) is definitively designed to favour a certain direction - hence the gearing bias and need to fit the higher rolling radius to the rear.
It just would not be able to rapidly revert to normal operation otherwise.
I apologise for my lack of Portuguese my friend,
Joe

Ok. So knowing that with the freelander it is best to keep all tyres equal or second best have newer tyres on the rear ....

What is the best way to incorporate rotating the spare to ensure it wears at an even rate with the rest of the tyres?

Is it best to just rotate the rear tyres with the spare every few thousand miles?

I can see there being the issue of getting a flat on a well worn tyre and then putting an unused spare on and it playing havock with the drivetrain.

If you check out the link that I posted earlier you will note that there is a 5mm tolerance limit in the VCU. So you could possibly get away with keeping a half worn tyre as the spare as long as you only use it to get yourself out of trouble and repair the flat ASAP.

Easy, keep a half worn spare on the back

Also, beware of the naysayers about fitting the spare ! the is ABSOLUTELY no issue in fitting even a full tread spare in the event of a puncture - non at all
So much hyperbole talked here about this.
The issue is simply that a difference in rolling radius over a PROLONGED period of time may cause issues - not in the short term.

Hell, just get a few pressurised tyre inflation kits from your favourite motor store and be done with it.
The way some talk here is that a small issue is going to wreck the IRD - I say Bollox ! utter total Bollox ! - porlonged - possibly - but normal use - not an issue at all.

Treat a spare as a spare;

The vcu will and can cope with all the above - quite happily with no adverse consequences - PROLONGED use may cause issues - however you are talking thousand of miles - not a few miles to the pub- anyone saying different is again talking utter bollox !

Thanks! That's good to know

I'm with Joe_H on the spare tyre issue. Just fit it wherever you need. The VCU should have a sufficient safety margin to tolerate the spare, even if it's new and is replacing a worn tyre. The VCU will only see an average of the 2 tyres on the same axle, so it really shouldn't matter, in the short term at least. As said, use the spare as a spare
There have been instances where Michelin Synchrone tyres have caused problems but I think that is when 2 non Synchrone tyres are fitted. The Synchrone has a vastly different rolling radius to most other tyres of the same marked size. I have a new Synchrone as a spare on my Freelander, and don't give its possible use as a spare a second thought.

With a Freelander, the most important issue is keeping the tyre pressures the same, on all four corners.
I don't think it's practical to start debating specifics, ( e.g. such as 1mm difference between tyres etc. Rotation is academic). i.e. Who is going out in the winter months to suddenly change over all their tyres because a certain amount of mileage has been realised?. A weekly check on tyre pressure, including the spare will achieve the same savings as any amount of farting about with switching them over.
I've recently replaced all mine on a '55' Freelander 1. They were the original fitted tyres as far as I know and the treads were fine. However, examination of the walls showed quite severe cracking. They were also getting noisier on each journey. Having replaced them, it's now like driving a different vehicle, quieter, smoother and they actually look better.

Tyre rotation. I bought a set of tyres in late 2014. However, at that time I couldn't afford a new spare. I swapped the front with the rears and moved them diagonally every 3 months. In mid 2015 I purchased that new spare an popped it straight on the rear axel, making one of the rears the spare. I've clearly marked that new spare and it gets swapped from L to R on the rear axel and I rotate the others clockwise every three months. I also keep a close eye on tyre pressures. I have Bridgestone 205/70/15 ATs 697 and run them at 28psi. This is a wee bit less that the fitters put in which was 32psi. My reason is that I commonly see tyres worn our in the centre of their tread due to over inflation and there's still good, legal tread on the outer edges.

I've just bought a second set [5] of mud tyres: 215/75/15 Maxxis Mts. I already had a spare set of rims waiting for them. These are not far off the original factory tyre size of 195/80/15 ATs in rolling distance and height. I'll manage their rotation carefully too. More systematic that my slightly muddled arrangement above.

Between tyre pressures, rotation and keeping a eagle eye on the coolant level / temp' situation you can justifiably call me paranoid! I looking at fitting a tyre pressure monitoring system too!

Tyre rotation in New Zealand.
I have just traded my 2002 Freelander 3 door TD4 for a 2007 Freelander 2. On my first FL I rotated all five Michelin tyres clockwise round the vehicle every 10,000 kms. A set of Michelins would last for 125,000 kms. I bought a complete set of new Michies only twice and reached 300,000 kms before trading. Landrover tell me I rotated the tyres wrongly.
Really?
The vehicle lasted, the engine was fantastic, it just showed old age and lack of tender care.
Now, question is, do I do the same thing on the Freelander 2? Everyone says no, but hey, I got 125,000 kms per set on the first Freelander.
Anyone with similar experience?
Cheers
Bryan

Bryan Winters said:

Tyre rotation in New Zealand.
I have just traded my 2002 Freelander 3 door TD4 for a 2007 Freelander 2. On my first FL I rotated all five Michelin tyres clockwise round the vehicle every 10,000 kms. A set of Michelins would last for 125,000 kms. I bought a complete set of new Michies only twice and reached 300,000 kms before trading. Landrover tell me I rotated the tyres wrongly.
Really?
The vehicle lasted, the engine was fantastic, it just showed old age and lack of tender care.
Now, question is, do I do the same thing on the Freelander 2? Everyone says no, but hey, I got 125,000 kms per set on the first Freelander.
Anyone with similar experience?
Cheers
Bryan

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That's only about 6000 miles, so the difference between front and rear tread wear will be negligible, especially if your mainly driving on tarmac.
I'm no expert on the FL2, but I believe the Haldex system is less temperamental than the vcu.
So, if it works for you, go for it.
Although I would like to point out, it's not my fault if it breaks
Mike

FL2 can be rotated. I rotate the wife's Ford Kuga tyres which uses the same 4X4 system as the FL2

Skinny Mike said:

That's only about 6000 miles, so the difference between front and rear tread wear will be negligible, especially if your mainly driving on tarmac.
I'm no expert on the FL2, but I believe the Haldex system is less temperamental than the vcu.
So, if it works for you, go for it.
Although I would like to point out, it's not my fault if it breaks
Mike

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Thanks Mike,
you've opened a door on haldex vs vcu. I'll look into that. I think my main point was a history of getting a long use out of a set of tyres. Are any others getting 125,000 kms per set? (78,000 miles)
Cheers
Bryan

Bryan Winters said:

Tyre rotation in New Zealand.
I have just traded my 2002 Freelander 3 door TD4 for a 2007 Freelander 2. On my first FL I rotated all five Michelin tyres clockwise round the vehicle every 10,000 kms. A set of Michelins would last for 125,000 kms. I bought a complete set of new Michies only twice and reached 300,000 kms before trading. Landrover tell me I rotated the tyres wrongly.
Really?
The vehicle lasted, the engine was fantastic, it just showed old age and lack of tender care.
Now, question is, do I do the same thing on the Freelander 2? Everyone says no, but hey, I got 125,000 kms per set on the first Freelander.
Anyone with similar experience?
Cheers
Bryan

Click to expand...

Welcome Bryan, yes we rotate tyres clockwise down here - they rotate them anti clockwise in the northern hemisphere. Just one of those funny differences between the hemispheres. Like the direction water swirls down a plug hole and as Paul Henry was saying yesterday about dogs turning around in circles before they take a dump, its because they are trying to determine north - as dogs will only do a dump facing north - but its south in the northern hemisphere.