4.8is cold shifting = very jerky

[brucemillar]

Folks

Apologies if this has been asked, but I didn't find it.

My 4.8is (2006 e53) is very jerky when pulling away from a standstill in these colder mornings (>3.0c)

Is this just how it is when it is cold? It is noticeably jerkier (is that word) when in Manual/Sport mode and does seem to want to make a hell of a lot of shifts. Once the car has warmed up it is not so bad, although the box does still seem very random in its approach to shifting at times.

So, if in Sport Mode, but NOT using the sequential shift and just letting it do its own thing, it will hang on to 1st gear for way too long, meaning the engine really revs. This has the effect of others thinking I am showing off (I'm not honest) as it revs the hell out of itself between traffic lights. If I leave it in Normal 'D' then it is fine.

I am assuming that there is no dipstick for the trans, so I would need to check the level by climbing underneath and undoing the filler and seeing it if spills any ATF?

The car is a low mileage = 87k Miles (checked out) and full BMW Dealer Service History. I see no record of any ATF or filter change.

I know that BMW often say "sealed for life" and that this often proven to be not correct or smart to adhere to?

Is there any software that I should be looking at for the shifting? or is it purely fluid and levels that I should look at?

Many Thanks

Bruce

[wpoll]

Holding the gear longer is normal for Sport mode - that's why it's "sportier". I don't tend to use it much, especially on a cold engine. Mainly when towing up hills...

There is a very specific procedure for checking the trans fluid level - it involves having the trans as a very specific temp, the engine running and checking the level via the fill port (either on the pan or on the side of trans body - it varies). Not something you can do at the local servo after filling up....

Pros and cons for and against servicing the trans. - many folk have gotten results from a service but others have had major issues.

Yeah, a good ZF 'box is a beautiful thing - and old one with issues can be a 'mare and spoil an otherwise wonderful car.

[wpoll]

Oh, I should have added that mine (a ZF GA6HP26Z) is pretty good when cold - a little different than when warmed up but not a big difference. Certainly not jerky, even when moving from D to R or back again. 212,000kms and never cracked open (as far as I know).

[Qsilver7]

There is a cold engine warm up mode where RPM is high and the shift to 2nd is prolonged. This is to help the transmission and engine warm up quicker. If possible..try not to force the vehicle out of this mode (which can make for an abrupt shift)...try to keep the RPM under 2K until it shifts on its own.

Take note of the 3 bullets in the info below. Again, if you force it out of engine warm up cycle by going faster than 25 MPH, or revving higher than 2K, etc...then you may get an abrupt shift. I find going into sport mode (shifting over to the S/M gate) helps prevent the abrupt shift if it is necessary to force the vehicle out of warm-up cycle:

[wpoll]

Originally Posted by Qsilver7

There is a cold engine warm up mode where RPM is high and the shift to 2nd is prolonged. This is to help the transmission and engine warm up quicker. If possible..try not to force the vehicle out of this mode (which can make for an abrupt shift)...try to keep the RPM under 2K until it shifts on its own.

Take note of the 3 bullets in the info below. Again, if you force it out of engine warm up cycle by going faster than 25 MPH, or revving higher than 2K, etc...then you may get an abrupt shift. I find going into sport mode (shifting over to the S/M gate) helps prevent the abrupt shift if it is necessary to force the vehicle out of warm-up cycle:

Doh! Yeah, totally forgot to mention that I never warm up my car (by idling) but always drive under 2,000rpm and 40-45km/h until the temp gauge gets up above the blue (about 45Deg.C). Quarter mark is 60Deg.C. Maybe that's why I don't get any jerking etc..

[pearlpower]

Very likely the solenoids, they are garbage in these transmissions, just about the worse solenoids I have encountered. For them to go south at 30k is common. Jerky shifts, even when cold, is a solid symptom they eventually they will need replacing.