I belive the BM box you are refering to is the ZF 22HP4, (don;t even need to read the posts to work that one out!) ZF didn't fix the box in '92, they just relaesed a fix for the porblem, which is to drill a new oil way to relase the excess pressure to the 1st gear clutch pack. This was not applied to any of teh production of this box.

For all the talk of German 'quality' this fix was found by Jaguar while testing the XJ40 in the early 80's and in fact applied to every box to enter browns lane beofre it was put in a car and only accepetd by ZF in '92 as a valid fix (When jaguar stopped using it and went to the 24HP4!). None of the other users of this box used the fix, the result is, it fails in range rovers, Volvos and BMWs but in the Jaguars normally outlasts the car. The only conection between the 22HP4 and the 18HP4 is that is does not use brakebands like the older autoboxes but clutches instead, the 18 I belive does not suffer from root cause of the 22HP4's main problem whcih is th failure of the seal allowing constant pressure on the 1st gear clutch pack in N and P, oh and R! I have rebuilt a few of these from range rovers, and its always the same clutch pack that has disintegrated! I wodul like to see a failed 18HP4 to see what the root cause of failure has been, but I belive it will turn out to be overheated or dirty fluid as my current VSX has 160K on the original auto box but has had the fluid changed every 7K and I don't belive the cooler fitted to the box is that great, not to mention failure of this cooler allowing water into the box won't do it any favours either

Stewart

Apart from regular changing of the fluid using the correct brew, is there anything to
take out of all this that would help prolong the life of the box by adopting a particular
driving method/style?

Dammit, even thinking about how I should be using an autobox is more hassle than
a manual even where you're supposed to be doing less!!

Andrew

On whether to use N or D at lights - I notiice a very slight vibration in D which reduces when I slip into N. This was true of my '92 car and is also noticeable on the 2000 version. To me this means the box is working more in D than in N so producing more heat, wear etc., also the car is trying to move forwards gently when in D so stopping it surely can't help. Anyway what do I know, I'm not a mechanic!

To those who leave their feet on the brake at lights, I hope you mean the parking brake, if not you must be the *** s who dazzle following drivers!

I also believe in changing the box fluid at every srevice. It is possible to get about 4-5 litres at a time out by sucking it out through the dipstick hole, using a thin plastic tube. I use the input to my compressor for the suction (via a collecting jar - an ex-winemaking demijohn- to prevent fluid being sucked into the compressor). One of those maual suction thingys from machine mart may also work. You only get about 3 litres out using the Haynes method.

For the record the '92 car lasted 190k miles, the box was still silky smooth but liked to change down on average hills, not sure whether the box was at fault or the engine was losing it's youth. The 2000 car is happy to stay in top on those same hills but is not such a smooth changer, hence the paranoia about changing the fluid.

Yes, that's about it in a nutshell.

I understand it has a series of programs, six i think but I'm too lazy to check, ranging from ultra economy to sport and it selects the program according to your recent driving style. That's only one of its tricks of course, for instance it also tells the engine computer it's about to change up and to reduce engine power momentarily.

I think I'll cary on as always, selecting neutral at traffic light stops on both my gearbox types 4HP18 and 4HP20. I never select park since a close shave when I thought I'd got neutral, moved the lever back one notch and very nearly collected the car behind me when I moved off!

Derek

Does my 98 estate have the adaptive box does anyone know

Norman

There was a comment that the Diesels didn't get the Adaptive box.

You will know though, as it should have a Snow/Ice switch ahead of the Suspension Sport/Normal switch on the centre console



Rgds

C

The box on my 1992 S1 3.0 estate gave upon me last week. I also have a 1996 S2 2.0 TCT that has a number of faults but a sound (as far as I can tell).

Has any body any idea whether or not the box from the 2.0 would be ok in the 3.0?

Will

1992 3.0 SE Estate
1996 2.0 TCT VSX saloon
1998 Mercedes E280

Norman,

The answer is no, i'm afraid.

Robert

Hi Norman, as robertxmb says, no. The autoadaptive HP20 was only ever fitted to late series xm v6's and only those with a multiplexed electrical systems according to citroen's laser manual.Also only 500 or so multiplexed xm's, orga 7490 to 79XX were built, all LHD, and no export models.

Oncw again, I don't know if I'm missing something here, but Will's V6 is a '92 model and never had the auto-adaptive box. As far as I know it had the 4HP18 which is the same box as the TCTturbo.

Derek