Thread: CDL in D2

My experiences from driving with a blow rear diff.... is that the front end has surprisingly little traction, and when climbing it will have next to none.

The rear diff has most of the weight of the vehicle sitting on it and it will provide a lot of the drive as it generates most of the traction. If you are spinning tyres already, 1 front and 1 rear.... then the rear will have more to offer.

I appreciate Slunnies explanation. I used to think that made sense. My brother who fits them for a living has a different view to the theory that rear first is best. It seems that particularly IFS benefit from front first. I did say it was up for debate - I wasnt dogmatic about it (although I suppose Slunnie can be more 'dogmatic' ) Here is an explanation from http://www.pps.net.au/4wdencounter/a...ifflocks.html:


"So now your aware of the differences between the types of lockers avaliable, which is the best place to fit a single diff lock, front or rear? This is actually a loaded question as it depends on the type of terrain and your vehicle type, but in a nutshell I believe the front is the best place. This is especially so for independent front suspension vehicles which easily lift a wheel even on modest terrain. Additionally, most vehicles these days already have a rear LSD so why fit a locker to the rear and leave the front diff open? Its a better option to fit the locker to the front and leave the LSD in place. When the vehicle has open diffs back and front there are still advantages for a front fitment. When in sand or mud the fitting of a locker to the front will have a greater effect. If hill climbs are your main speciality then a rear fitment may be a better choice as there is a significant weight transfer to the rear axle when going uphill. However if the hillclimb requires large rocks, gullies or shelves to be driven over, then a front locker will drive over the obstacle rather than being pushed up it from behind. As you can see, there is no right or wrong answer, just different choices depending on individual factors. "

Having said all that a Disco is a Disco and has light front end and good travel and live axles front and rear, so I would be more inclined to follow people like Slunnie than the general theories, but have a think about your driving and where your likely to go before committing.

Cheers

yeah i can agree with what that article says. slunnies points are validated re- hill climbing, but for the muddy/sandy gear and can appreciate the extra stabilty and "pull" a locked front end would give.

Originally Posted by ozscott

The manager put it down to this - the fact that the ETC was trying to brake wheels and it was possible that it would brake in such a way that the drive wasnt properly distributed and it put strain back on the box. I said well whats the go with the Extreme and he said that LR had told them that the software program for the D2 with no CDL was much more aggressive than the Defender and that CDL in the D2 was certainly not compatible.

I know that quite a few people have installed CDL into their D2, but I have never quite resolved all this in my mind. I suppose that if 2 wheels on the same axle braked simultaneously with CDL engaged that could cause a problem.
Cheers

This is effectively what I was told by both mechanics (one LR trained, t'other an independent).

UP.....thanks heaps for your indepth reply, it was more than I expected when I popped the question. It has more than cleared it up for me.

Can you explain the quote below from your later post...what is the SLABS ECU and where is it?

I had heard yrs ago on Overlander Forum that there was a re-wiring mod to that involved a jumper from the ?CDL warning light to ??? (can't remember) to solve the problem. Slunnie might know as I think he was involved in the thread.

UP wrote:-
You can eliminate this problem totally by cutting the wire from the diff lock switch that goes to the SLABS ecu, that way it does not matter when you engage the CDL. This is how the 03 / 04 's are, I can start / stop, disengage / engage etc any time, and the 3 amigos never come on.

cheers and thanks again

SLABS ECU --- Self levelling Anti lock brakes ECU

Hi to get to the wire,

remove the trim under the glove box. There you will find 2 or 3 ECU's depending on the spec of your vehicle. The SLABS ecu is most likely the centre of the 3, now find the black / blue wire running to pin 9 of the plug, it is the central pin on the lower row, You need to cut this wire and either tape the ends, or as I did fit some "bullet" connectors to enable it to be re-connected at a later date if required. Make sure you have the correct pin / wire BEFORE you cut it.

What this does is stop the SLABS ECU putting the 3 amigos on (ABS ,TC, HDC) lights "if" you start the car with the difflock engaged. If you cut the wire the car dont care if difflock is in or out.

And despite what you may have heard previously, if you don't cut the wire and the 3 amigos light up, it is ONLY the TC that is fully inhibited, the ABS and HDC still function, but at reduced parameters.

Some people like it this way, no idea why, imo CDL and TC is the best of both worlds and as close as you'll get to lockers in your diffs/

Originally Posted by green man

I have just fitted the linkage from an '03/'04 model to my 2000. I have been advised NOT to use the diff lock without first disabling TC as there will been opposing forces (braking v driving) if TC is working. Two mechanics have told me this but I am getting different opinions from users in the field. I'd be interested in opinions here.

Begs the question....what happens in the '03/'04 models when CDL is engaged? I imagine there are differences in the computer settings from '00 to '03


many thanks

TC is all about opposing forces... TC wont hurt CDL at all, just improves overall performance...

Just use it and enjoy...

I have a momentary switch I use when re-starting with CDL locked so that I can keep it locked and have CDL/TC

Originally Posted by green man

I had heard yrs ago on Overlander Forum that there was a re-wiring mod to that involved a jumper from the ?CDL warning light to ??? (can't remember) to solve the problem. Slunnie might know as I think he was involved in the thread.

UP wrote:-
You can eliminate this problem totally by cutting the wire from the diff lock switch that goes to the SLABS ecu, that way it does not matter when you engage the CDL. This is how the 03 / 04 's are, I can start / stop, disengage / engage etc any time, and the 3 amigos never come on.

cheers and thanks again

All I did was picked up the CDL wire from the transfer case and included a switch into it which I put on the dash. When I start the disco with the CDL locked, then I just open the switch while starting and then reclose it. This allows the CDL dash light to be maintained.

I really like UP's mod as detailed here. I had heard of this mod before, but access to the wire was a lot more complex and required disassembly of the centre console. UP's mod would most definately now be the way to do it as it maintains the CDL light on the dash and does not require driver intervention unless you wanted a situation where you were looking to disable ETC. I haven't yet found any time where nonETC is better than with ETC.

Sounds like a great mod Once again.....many thanks for all your input I'll take a look on the RAVE CD for the SLABS ECU.

Daryl