2004 4.4 sport in for inspection II - gearbox query

[gchristofi]

Hi All

rightly or wrongly??? i decided to keep up the full BMWsh on my motor so today it was in at the stealer for the full inspection 2 service. When I dropped it off, I mentioned that I still had the gearbox lurching issue (which I've read up on where I can) so could they please investigate.

(Last year, I did get the stealer to upgrade the Gearbox control unit to the latest version but this didn't fix the problem)

I got a call this evening saying that there was another process called adaption which they could try and that they can also change the Transfer box oil for an extra £135. Hmmm.

I'm presuming they are talking about resetting the gearbox in the same way as the well publicised 'ignition in pos 2, foot on accelerator for 20 secs' technique which I have done several times to short term improvement, but what of the transfer box fluid??? Is this a good Idea? Is this the same thing as changing gearbox oil? Might it work? Might it cause catastrophic failure????

All advice welcome as I'll be calling back in the morning to tell them what I want to do.
Cheers

[X5Sport]

Sounds a bit like they're clutching at straws. I can't see how changing the transfer box fluid is going to make any difference other than put nice clean oil in it.

The gearbox rebuilder ran through this re-adapting process with mine when it came back as it was lurching. They then changed the Mechatronics Unit too, with little improvement. Eventually another replacement box plus another new TC was fitted, end of problem.

I was talking to the rebuilder yesterday as they have a look at the gearbox again 6 months/6,000 miles after the repair as part of their warranty. He currently has 4 BMW's and an Audi, all with the ZF 6speed for repair. The failures seem to be in the torque converter with either the damper unit (takes up the jolt when changing gear?) or a one way clutch within the TC being the most common failure. Mine was the one-way clutch that failed and lunched the box.

I wonder if it's possible that you may have a damper issue? Purely a shot in the dark as I don't really know.

Whatever it finally turns out to be, I have some serious doubts as to the longevity of these autos, or some of them at least.

Hopefully yours is a simple fix, and an official re-adaption plus software reload will do it, plus the new oil of course.

[AW8]

Assuming its first Insp 2 @ circa 60k I would go with the ATF change.............mixed view pros & cons but makes sense if thats the rough mileage. Plus if done & it later goes bang you would have better grounds than most to ask for goodwill towards/for a new box on back of dealer recommendation & FBMWSH assuming hiostory spot on thus far.

Iirc X555 had positive results from a dealer transmission update..........if he doesnt post here maybe send a PM

Fore more discussion google "the lurch" to see more chat including from Jag owners.

[jas328sport]

Not sure what difference if any it made but my x had had the transfer box fluid changed by the main dealer before I bought it and I had absolutely no gearbox issues in the 13 months of ownership other than the usual dropping down a couple of gears when touching the brake whilst going down hill. I have never had any signs of the lurch that people talk about even though it had done 74k.

[x555]

I had the transmission update from the dealer as AW8 said but didn't reply as you said in your op that they had already done this.IIRC it was about £70 and it made a world of difference for mine though it has never totally cured it and i still evety now and then get a good 'thud' to remind me.
The biggest difference for me was the lurch down into first gear as it used to 'jerk' into first after coming to a stop....again it still does it but not nearly as bad!!! i think it's a combination of the trans update and me getting used to it aswell.... i have come to accept this as a characteristic of the car

What type of lurch do you have ?
More info re lurch here..... http://www.thelurch.com/lurching_zf_transmission.htm

[gchristofi]

Thanks for all the input. X5sport, clutching at straws sounds about right to me. Initially when I phoned back, they said that the change of transfer box fluid was an option on Inspection 2 if it 'hadn't been done before'. They also recommended an 'electronic adaption' followed by a road test. I quizzed them as to whether this would be any different to to the reset process much discussed online, and things got a bit fluffy. I asked about changing the ATF as a possible solution but raised concerns regarding potential risks of further trouble at which point the service manager said he would consult the tech.

They have since phoned back with advice not to change any fluids (surprise surprise) but to 1st have the electronic adaption done and see how that goes (£80!). I left instruction that this should only be done at my cost if it was a different outcome than the reset using the accelerator pedal (which they said was an engine reset??) We shall see what happens but I remain pessimistic.

All this expense in the hope that should the time bomb go off, there's some manouvre left with good will. Yes AW8, this is the 63k inspection 2. I'm pretty sure I saw a recent post by someone with a dead gearbox on a 2005 3.0d with 42k miles and BMW didn't even entertain the good will request. Perhaps I should forget flushing the box and stop flushing money down the drain on Dealer History?

As you say x555, once you accept the characteristic you can drive around it, but it is still annoying holding off the accelerator until you feel the clunky downchange at roundabouts!!

[gchristofi]

Well, so far, the 'electronic adaption' to the gearbox does seem to have improved things greatly. I've only driven about 20 miles so there's always a chance the demons inside will learn their bad habits again, but fingers are firmly crossed. I hope not because I don't facy paying £80 every time to reset adaptions. (They insist that the accelerator pedal reset works on the engine and not the gearbox.) Anyone got any home equipment that could do the reset?

The transfer box fluid change recommendation is described as follows on my schedule... : if entry "54C6" is stored in fault memory, replace transfer box fluid (0,76)1) ....
A little digging around suggest 54C6 suggest a poor reading of fluid quality but does any one know exactly how this is measured, i.e what are and where are the sensors? Perhaps it's tied to the Trans/failsafe prog error which I've seen a few times?