Thread: Latest LRO International Mag - article on Diff lock D2 or not

I have recently fitted the CDL cable from an '03 wreck and look fwd to using it this weekend. I love the TC...when I first got the D2 (after owning a D1) I was v.impressed with its ability to get places (read Gembrook mud) with the std Michellins that the D1 would not go with decent ATs.

However whilst reversing downhill through the brakes once I got crossed up at 45 degrees on a 30 degree slope...not much fun. The only way out was to accelerate to induce drive to the front wheels so I could regain steering, having done this the truck straightened up of its own accord and I continued down in a straight line. That experience convinced me to get the CDL linkage fitted.

As for HDC...never had a real issue with it, it has always been effective for me and I have an auto


cheers

Originally Posted by Disco44

After reading about the problems of the computer based D2 Geez I'm pleased that I have a D1 in that I have complete control of both going up and down hills and other obstacles The bush is the bush one cannot change it..one worries if anyone that designed these vehicles have ever been there....its a bloody long way home for a modern busted electrically computer controlled vehicle

I personnally don't like using the HDC, but, the missus does and we have never had a problem with it, all this rubbish about the car taking off for no apparent reason has never happened to our D2.

We had the TC only for about 5mths before i fitted our first CDL (AMV electric one first) and never had an issue with HDC and still haven't, the Disco is 7yrs old now.

Baz.

I can only agree that a CDL is the way to go. It is a mechanical lock. The ETC is reactive, so in those difficult off-rd situations (such as a steep climb) with ETC you have to lose traction before you can regain it, with ETC alone it just is asking too much. A centre diff lock means that at least one wheel on each axle is receiving drive without interruption.

I personally love ETC and think it is the best, convenient all-round traction aid for off-roading in standard 4WDS that are also used as everyday road cars - there is no doubt that one ETC equipped will go much further, much more easily off-road, with ETC.

Consistantly loose surfaces, such as sand, can be another thing, where ETC can be frustrating in the way it can kill momentum, especially the early systems. If you know what you are doing, you can usually plan ahead and drive around this problem. ETC is not a complete off-road solution, but tell me what is for all-round road and off-road use.

BUT it has to have a part time centre diff engaged or a full-time centre diff that is locked (or a viscous, I suppose) to be any good.

Some of the comments about TC make me wonder if there are differences in the systems over the years...and in the maintenance of the ABS modulator. I recall an article in a South African LR site where a tester got ahold of an early D2 and thought the traction control was crap. Turned out it had an undetected ABS modulator fault (that didnt throw any lights) and it was fixed and he was asked by LR to take it back again. He then did and had to admit he was marvelled when it, amongst other things, forded and river and then climbed a steep slippery mud bank on the other side where his own 90 with mud tires gets stuck in the same conditions - and he made the comment that the D2 had road tyres on. He was a convert.

I have a D1 unlocked to compare my D2 unlocked to. I have done trails in both that leave them both spinning and going nowhere, but I have to say that despite the D1s better articulation the D2 will generally go further where there are axle twisters involved. Its a simple matter of crossed up and no drive for the D1 and trying to bounce he through is inviting damage and sometimes is just impossible.

With my D2 the TC will operate in low range with no throttle, but apply the throttle and it works much harder. The trick is not to apply then get off, but to apply and either hold or go a little harder but not to back off alltogether - it cuts out when backing off completely and you then loose the advantage for a few moments.

Personally I like it. Yes ideally I would like both CDL and ETC, but overall its a very good system.

I have used the HDC many many times in steep downhill situations where with it off, despite a manual trans, it wants to play up, with it on it tidies things up nicely. If it runs away, then either the gear selected is too high (see the tech articles about how HDC operates - it has different profiles for different gears and will run off in higher gears to a higher pre-determined speed) or there is a problem with the system.

Cheers

Trouble with off-roading is surfaces change so much it's hard to gauge sometimes if it's the vehicle that is better or worse, or the track that is better or worse, especially in convoy situations. I never like being the last in a convoy - because a piece of track that looks like a highway for the first vehicle can be very 'off-road' for the last...

I have tested a LX470 once on a slippery, steep set-piece ramp. I had it in low range but forgot to engage the CDL, thinking it was locked automatically in low-range.

Well, its ETC was groaning and whirring away like crazy, with me holding a fairly assertive throttle position (like ozscott says, you can't pussyfoot around with ETC in high-load conditions - you have to keep your foot into it).

The LX was going nowhere, so I gave up. About to reverse off the ramp, then realised the CDL was not engaged. Hit the button, tried again and it walked up easily, with only slight help from ETC.

I dont know about the LC but the Defender Extreme's traction control program is not anywhere near as aggressive as the unlocked D2's program - I assume, but dont know, that the same applies to the D2a with its CDL from the factory.

As such I would expect an unlocked Deefer or D2a to not be as flash with CDL unlocked and relying on just ETC when all crossed up than a D2 without CDL all crossed up. Of course with CDL engaged you would expect the first 2 vehicles to be a bit better again and certainly with less theatrics and a more positive feel.

Cheers

Originally Posted by ozscott

I dont know about the LC but the Defender Extreme's traction control program is not anywhere near as aggressive as the unlocked D2's program - I assume, but dont know, that the same applies to the D2a with its CDL from the factory.

As such I would expect an unlocked Deefer or D2a to not be as flash with CDL unlocked and relying on just ETC when all crossed up than a D2 without CDL all crossed up. Of course with CDL engaged you would expect the first 2 vehicles to be a bit better again and certainly with less theatrics and a more positive feel.

Cheers

The ETC on the D2, D2a V8 and TD5 and Defender TD5 is excactly the same, it was only when the D3 came out it changed, the ETC in the D3/Freelander2/RRS is outstanding and reacts much faster than the older ETC.

The LR ETC is by far the best system in 4WDs today, it make the Defender and D2 a much better vehicle offroad.

This is where ETC comes into it's own, when you have wheels off the ground in deep holes like this one, not many 4WDs will drive out of this without some momentum or a locker.


After listening to a Prado going up a slippery hill when down at Jenolan SF, i'm glad i've got the LR system i thought the bloody car was falling apart, turned out it was the Prados ETC working

Baz.

Cheers Baz. I am going on what a mate of mine who was the service manager for a top LR stealer for many years (and before that on the LR tools) up until a couple of years ago told me - ie re the difference in computer program between the deefer extreme and 'unlockable' D2; there are no physical differences just program he told me.

Cheers