Gearbox Question.

[crockers]

I have the 7 speed auto. On Monday had the A service. Have noticed a few clunky down changes ..so when I got a call on Wednesday asking how I felt the service was - I asked had they flashed the 'box with new software. They said no so I explained that occassionally (not often) I get clunky downchanges from 2nd to 1st in slow traffic.

Car going in on Monday for them to look at it to see if there is a problem.

My question is .. if it needs a software update - should that have been done during the service? Had a technician call me yesterday to discuss and he talked about maybe needing to change the adaption..(to be honest I can't 100% remember his exact words) but said that's about 1/2 hr work as is downloading software.

Does anyone else have a similar problem..well problem is too strong a word as I can easily live with it - just dont want it to turn into something major. It was in the past so silky smooth...if it happened all the time I would be worried (more than I am) but it is very intermittent.

 

[rf065]

My question is .. if it needs a software update - should that have been done during the service?

I had an A service from MB 2 weeks ago, when I picked the car up they told me they had updated both engine & gearbox software as part of the service.

Russ

 

[bdabdabeav]

the earbox your referring to is a 722.9 and on recent cars i.e 204,219,164 we get several complaints of sluggish downchange or a hesitation when selecting reverse. This isnt a recall as of yet but generally out of goodwill a quick test should be run every service and updates checked for. the ETC update taks about 15mins and should cure the fault if not then it is possible the adaption values will need clearing and the car road testing to relearn the values this can be a lengthy process as you need a long stretch of road in order to coast with no accelerator input to allow the car to downchange 7-6 6-5 etc. no cost will be incurred to you in any of this.
regards

 

[crockers]

the earbox your referring to is a 722.9 and on recent cars i.e 204,219,164 we get several complaints of sluggish downchange or a hesitation when selecting reverse. This isnt a recall as of yet but generally out of goodwill a quick test should be run every service and updates checked for. the ETC update taks about 15mins and should cure the fault if not then it is possible the adaption values will need clearing and the car road testing to relearn the values this can be a lengthy process as you need a long stretch of road in order to coast with no accelerator input to allow the car to downchange 7-6 6-5 etc. no cost will be incurred to you in any of this.
regards

Thanks for this input - mine is a W203 C320 cdi and is 2005 so is out of warranty.

 

[davidjpowell]

I used to get a 'jerky' first change on mine. Apparantly a known issue. The dealer would reset it, and it would generally come back.

I did have one very strange 'clunk' on a low speed downchange. Not sure if it was related, but it was after a peiod of 100mph driving (Germany) followed by a period of gentle driving on the old tank roads.

I described the fault to the mechanic in Doncaster, who suggested it worth investigating. They drained the oil and found it to be burnt, so replaced the gearbox.

Hope all is well.

David

 

[evdok]

Dads CLS had this problem few months ago, ended up been a clip on a shaft which worked its way loose & moved along the shaft, out of warranty but managed to get a goodwill settlement & only paid £105 the rest of £1350!! (removed gearbox) was cleared by MB (2005 with 11,000 Miles)

 

[camerafodder]

I get the jerky 1st to 2nd change on mine, also stated by my dealer to be a known issue. It only happens when drifting along in slow moving traffic. When accelerating away from a standstill, hard or normally, the problem doesn't manifest itself.

 

[crockers]

Took it into the dealer today (and to be honest it seems to have stopped doing it) - they took it out for a run and could find no faults..said that the box is an adaptive one and that after they had test driven it they may have "taught the computer" a differing driving pattern.

But now it may have relearnt my (softly one)...

Does this make sense?? It now changes smoothly again...(in fact it only happened a few times after the service)

 

[kwakdonut]

Yes it is possible - they may well have 'reset' the gearbox (throttle position sensor actually) post-Service. Always seems to take anything up to 100 miles for it to settle down again after.

I reset the gearbox on my 270 a couple of times and it had always shifted its change pattern until it settled again.

Maybe this is the same as my wifeys A Class???

Hopefully, MB Swindon may be able to get to the bottom of my gearbox problem!