Autobox hard change 2 to 1 when cold

[Grahamcol]

Hi, My 2000 C280 W202 Tiptronic sometimes makes a very hard shift 2 to 1 but only when not fully warmed up. What seems to happen is that I'm in traffic and slowing down in 2nd with little or no throttle and then I want to increase speed again so I apply throttle and then there is a very slight delay and the box then thumps into 1st and away it goes. Once hot, the box is silky smooth. There are no oil leaks underneath the car so I don't think the box oil level is low although I guess it would be an idea to check this. I've read somewhere about this with this model but can't find it again now. Is this normal ? Ideas anyone please. Thanks.

 

[Adam230K]

Definately shouldn't be any thumping of any kind. I'd start by checking the oil level as you said because there isn't much else you can do..

 

[BlackC55]

The adaptation data can be re-set and this may help

 

[wemorgan]

As an interim you could try driving with the gearbox in W mode.
AFAIK this misses out 1st gear and uses 2nd as the lowest for a smoother ride.

 

[Grahamcol]

Thanks to those who replied. I guess the adaption re-set is done via star so I think the plan of action will be to book the car into my indie and get him to check oil level (maybe even change it + filter as car has done 63k miles) plus check the adaption settings.

 

[Grahamcol]

ps, also thought about using "w" mode which is, as said here, smoother. I'm just concerned that maybe this shouldn't be used all the time.

 

[Bobby Dazzler]

ps, also thought about using "w" mode which is, as said here, smoother. I'm just concerned that maybe this shouldn't be used all the time.

I've only ever seen this suggestion on Internet forums, but not in the manual.

I can't really see that it can cause a great deal of harm, and don't recall anyone on those forums having put forward a convincing case to support the suggestion.

Maybe one of our transmission experts might clarify?

 

[BlackC55]

Using W does no harm at all if used all the time.

 

[Grahamcol]

Thanks again for the responses. I will try it in W mode until the next service or something. I think the car has ample power (as it's a C280) and will still pull away from rest OK in this mode.