gear box 2nd to 1st gear slam
 

bmw e53 gear box Car never does it or has any symptoms when **cold** and gets progressively worse as it heats up

gear box 2nd to 1st gear slam

any thoughts would be greafull:thumbup:

Replacing the solenoids, mechatronic sleeve, and seals inside the trans usually sorts this problem. I have to do the same to mine but I drive around the problem currently. Never does it manually shifting or if I come to a complete stop at every stop sign, light, etc.

It would be helpful if you inform the group as to what type of engine you have. Each engine group used a different box. V8 engines normally had zf trans whereas i6 used the GM trans, don't know what the hell was used in a diesel, since diessel weren't that popular in the good ole USA.

If i had to guess something is not sealing correctly, either an o-ring or one of the drum has a leak or crack. When the trans is cold, the fluid can generate enough pressure but as it warms up the hydraulic pressure is less until it requires a great deal of engine speed to spin the trans pump to create the necessary pressure and then you get that"BANG" shift. Could also be a worn valve body, how many mileage is on the X?

150k mile
3.0d engine 2004

maf possibility
 

Believe it or not, when I unhook my MAF and drive my 3.0l, it shifts funny, but it really slams the shift from 2nd down to 1st. Hook it back up, and all 5 gears shift perfect up and down. Go figure.

Hi

The diesel has the ZF. We went through this as well. Highly recommend you address it asap as although you can cure the slam as Crystalworks said, the damage caused by the slamming extends throughout the drive train.

We had EPIC downshifts and didn't know how long the previous owner had left it like that.

Replaced the solenoids, the rubber seals and of course new oil, reset the adaptions and trans is smooth and operates like new.

funny you should say that
my map is un plugged at the moment due to it is not working and awaiting a new one.

That being the case, might try replacing the MAF before dropping the tranny.....Just sayin

yeah exactly . heard having a dead map sensor can lead to some erratic gear changes

The transmission computer does in fact use the map sensor as an input to help decide when to shift the transmission. the MAP sensor can affect the transmission shifting as ive been told