Disco II 2003 Diff Lock

Hi,

I am sure this topic has been discussed in details many times! However I still have few questions.

I recently bought a nice Td5 ES Premium 2003 (52 plate) manual gear. It has Traction Control and it doesn't have Central Diff Lock (the lever doesn't shift to left-no doubt!)

Now I have now three questions for you:

1) When I engage low ratio gear does the front and rear diff lock block?

2) As anyone any idea how to tell from the year, plate and model of the car if my one is one of those Disco II ready to be fitted with the central diff lock( I am not so sure I will be able to understand it by looking underneath the car) or if will require a substantive job. Can you also give me an idea of the price for these two jobs.

3) Once the Central Diff Lock is blocked what happen to the traction control. I can't see any button to use to press to switch it off. This would sometimes be equally useful regardless having a Central Diff Lock.

I am sure you wonder what I care about installing a Central Diff Lock if I don't either know the answer to question 1!:rolly:
...but this another story

Many thanks

Nic

you have no axle diff locks only the traction control which to be fair is very good , if t/box has diff lock facility it will have the spigot poking out the top of front output housing,if you fit a center diff lock you see need t/c control to stop drive been lost through a front and rear wheel spinning, hill descent relates to low box but not diff does

Dr LC8 said:

Now I have now three questions for you:

1) When I engage low ratio gear does the front and rear diff lock block?

2) As anyone any idea how to tell from the year, plate and model of the car if my one is one of those Disco II ready to be fitted with the central diff lock( I am not so sure I will be able to understand it by looking underneath the car) or if will require a substantive job. Can you also give me an idea of the price for these two jobs.

3) Once the Central Diff Lock is blocked what happen to the traction control. I can't see any button to use to press to switch it off. This would sometimes be equally useful regardless having a Central Diff Lock.

Click to expand...

Welcome to Disco 2 ownership

1) no when you engage low range it does not activate the CDL, doesn't affect the TC either, it purely just puts the gears in low.

2) upto but not including I believe 51 plates they were not factory fitted with CDL levers nor were they an option, but the spigot WAS in the transfer box (I.e get the new CDL/hi/low range lever cable and it can be fitted) if it has a CDL transfer box the cable can be bought for about £200-250. I think the face lifts 52 plates - 54's it became an optional extra. So you MAY be lucky and have the CDL transfer box but need to check/someone else enlighten you.

3) what do you mean central diff lock blocked?? Or do you mean locked?
The TC will still work when a CDL is engaged, but it will just not come on as much as it would without the CDL locked.
When off road the CDL and TC work VERY well together IMO and makes the D2 very capable.

UP's write up will explain it better for you

www.discovery2.co.uk/Factory Diff Lock

jamesmartin said:

you have no axle diff locks only the traction control which to be fair is very good , if t/box has diff lock facility it will have the spigot poking out the top of front output housing,if you fit a center diff lock you see need t/c control to stop drive been lost through a front and rear wheel spinning, hill descent relates to low box but not diff does

Click to expand...

Hi,

I am sorry but I am not so sure I got 100% what you saying...it is just my english that is crap

So you are saying that this car doesn't have any diff lock at all:nor front, central or rear? The only chance is to achieve a 50:50 by adding a central diff lock. However the traction control should control the spinning of the 4 wheel doing somehow a "diff lock job" on the three axels like the Mercedes G does or some of the Series 70 Toyota????? However it is my understanding that what a Traction Control system does is actually to stop the spinning wheel from spin but it doesn't transfer the traction on the opposite wheel. In this case it means that if one of the 4 wheels spins the other 3 are still...hence I loose drive.

Correct?

What instead I a not sure at all is what you are saying about hill descending system.

Many thanks again...

N

robhew86 said:

Welcome to Disco 2 ownership

1) no when you engage low range it does not activate the CDL, doesn't affect the TC either, it purely just puts the gears in low.

2) upto but not including I believe 51 plates they were not factory fitted with CDL levers nor were they an option, but the spigot WAS in the transfer box (I.e get the new CDL/hi/low range lever cable and it can be fitted) if it has a CDL transfer box the cable can be bought for about £200-250. I think the face lifts 52 plates - 54's it became an optional extra. So you MAY be lucky and have the CDL transfer box but need to check/someone else enlighten you.

3) what do you mean central diff lock blocked?? Or do you mean locked?
The TC will still work when a CDL is engaged, but it will just not come on as much as it would without the CDL locked.
When off road the CDL and TC work VERY well together IMO and makes the D2 very capable.

Click to expand...

Thank you. I use to have a Range 2002 Vouge similar to yours but I have never done anything similar to your in the the pics

1) My question was if there was a looking system on rear and/or front axel that would have automatically lock when the low ratio gears were engaged.

2) I just need to have a look at that.

3) yes I meant locked.

So how does a modern (Td5 onward) Defender works from this point of view???

Nic

Dr LC8 said:

Hi,

I am sorry but I am not so sure I got 100% what you saying...it is just my english that is crap

So you are saying that this car doesn't have any diff lock at all:nor front, central or rear? The only chance is to achieve a 50:50 by adding a central diff lock. However the traction control should control the spinning of the 4 wheel doing somehow a "diff lock job" on the three axels like the Mercedes G does or some of the Series 70 Toyota????? However it is my understanding that what a Traction Control system does is actually to stop the spinning wheel from spin but it doesn't transfer the traction on the opposite wheel. In this case it means that if one of the 4 wheels spins the other 3 are still...hence I loose drive.

Correct?

What instead I a not sure at all is what you are saying about hill descending system.

Many thanks again...

N

Click to expand...

if 1 wheel is spinning with no center diff lock all drive will be lost, with center diff locked you need 1 wheel on both axles to spin to lose drive , traction control will brake a spinning wheel which means that the other wheels dont lose the torque that would have been lost through the spinning wheel/s and so forward motion is maintained

robhew86 said:

UP's write up will explain it better for you

www.discovery2.co.uk/Factory Diff Lock

Click to expand...

Yes I know this article. Is one step ahead to me as it assume we know what we are talking about

Ciao

Nic

Dr LC8 said:

Thank you. I use to have a Range 2002 Vouge similar to yours but I have never done anything similar to your in the the pics

1) My question was if there was a looking system on rear and/or front axel that would have automatically lock when the low ratio gears were engaged.

2) I just need to have a look at that.

3) yes I meant locked.

So how does a modern (Td5 onward) Defender works from this point of view???

Nic

Click to expand...

there is no axle lock
defenders use a center diff lock and some also have traction control

jamesmartin said:

if 1 wheel is spinning with no center diff lock all drive will be lost, with center diff locked you need 1 wheel on both axles to spin to lose drive , traction control will brake a spinning wheel which means that the other wheels dont lose the torque that would have been lost through the spinning wheel/s and so forward motion is maintained

Click to expand...

Got it! So in theory TC is like having 3 diff locks or something like that!!!

Nic

Dr LC8 said:

Got it! So in theory TC is like having 3 diff locks or something like that!!!

Nic

Click to expand...

yes, the only draw back compared to having 3 diff locks is that with locks wheel cant spin separately with t/c they need to spin a fraction for brake to kick in , but on the plus side it doesnt hinder steering and its automatic so you dont need to select it

jamesmartin said:

yes, the only draw back compared to having 3 diff locks is that with locks wheel cant spin separately with t/c they need to spin a fraction for brake to kick in , but on the plus side it doesnt hinder steering and its automatic so you dont need to select it

Click to expand...

...and if the fuse goes you are stuck.

So by adding a central diff lock you separate the two axels completely reducing the work of the TC system. You also relay less on electronics and more on mechanic that is some circumstances can be safer...i'n it???:rolly:

N

Dr LC8 said:

...and if the fuse goes you are stuck.

So by adding a central diff lock you separate the two axels completely reducing the work of the TC system. You also relay less on electronics and more on mechanic that is some circumstances can be safer...i'n it???:rolly:

N

Click to expand...

In a nut shell yes, you got it.

Also CDL can be good for maintenance and if your prop's fubard or you break something whilst off road you can remove it, lock the CDL and still drive in 2wd.

Dr LC8 said:

...and if the fuse goes you are stuck.

So by adding a central diff lock you separate the two axels completely reducing the work of the TC system. You also relay less on electronics and more on mechanic that is some circumstances can be safer...i'n it???:rolly:

N

Click to expand...

never had a fuse go yet but any system can fail , adding cd certainly wouldnt hurt

The Discovery 2 with just Traction Control(TC) is very good off-road, but from personal experience I can tell you that if you add a centre diff lock (CDL) then the has to work less hard and you get better traction.

NB Remember that the TC work by using the the abs braking system (like on all cars) so it is vitally important that the brakes are in top condition for this to work well.

Good luck Nic


Dave

thebiglad said:

The Discovery 2 with just Traction Control(TC) is very good off-road, but from personal experience I can tell you that if you add a centre diff lock (CDL) then the has to work less hard and you get better traction.

NB Remember that the TC work by using the the abs braking system (like on all cars) so it is vitally important that the brakes are in top condition for this to work well.

Good luck Nic


Dave

Click to expand...

Thanks

Nic

Dr LC8 said:

...and if the fuse goes you are stuck.

Click to expand...

No, you just get out of the disco, crawl underneath and engage the CDL by turning the spigot with a 10mm open ended spanner ..... IF the CDL internals are in the transfer box.

(Then you find you're still stuck up a lane and have to get a tow due to the tyres not being up to the job on the terrain I was stuck on! )

There is an issue with using centre diff lock, where the difflock light signal affects the Traction Control. Late SLABS ECU's had modified software to get around this, earlier models need the light feed to be switched out, but you need to remember that the diff is locked.

That's my understanding of the situation.

Peter

Hi all,

Again on this topic. After all I checked and unfortunately my LRD2 is not equipped with any parts to fit the CDL. I need to buy the whole unit. Ideally I would fit an original LD model but I can't find any on ebay.
Can any of you advice on a model to fit?

Many thanks

Nic

listerdiesel said:

There is an issue with using centre diff lock, where the difflock light signal affects the Traction Control. Late SLABS ECU's had modified software to get around this, earlier models need the light feed to be switched out, but you need to remember that the diff is locked.

That's my understanding of the situation.

Peter

Click to expand...

You can cut the signal wire into the SLABS, that way if you restart the engine with CDL engaged the SLABS won't retard TC.

It's a right pain unless you do, in reality disengaging CDL is not quick, usually the drivetrain is wound up so you have to reverse for a bit to get the CDL to pop off, then turn of ignition and restart - of course in the heat of the moment you always forget.

A lot of folks retrofit the later SLABS unit.