So i recently flushed out my tranny and replaced the pan, filled with bmw tranny fluid till it was full, about 5 qts. The next day i drove it, it started to have harsh downshifts when i would come to a stop. Small "bumps" when i slow down, and another harsh "bump" when i stop. I have searched alot of places for answers but none that have fixed it. I have tried the tranny reset method, resetting the computer by unplugging battery and still no luck. Anybody have any ideas what is causing it?

 

forgot to mention it is a 2007 530xi.

 

"filled with bmw tranny" should be done in 2 steps
second step is on running engine
have y follow BMW TIS ?

 

Mechatronic (i think is what its called) sleeve comes to mind. Had the same issues w/my 07' 550i and that was what fixed mine.

 

do you have to drain the fluid to replace the sleeve?

 

How long ago did you service your tranny?
I had a couple hard up shifts... so I replaced the fluid and filter at an indy.... Upshifts were now smooth, however I had a hard downshift around 10-15 mph. Every time coming to a stop!! Lasted about a week.... I had to have the car sit for a couple weeks and now it shifts smooth up and down. Better than ever. Crazy.

 

I always thought the tell tale sign was when the Mechatronic sleeve was leaking you would get that downshift - well that's what I was told anyway.

 

I was told the leak was a result of the sleeve needing repair, i made an appt to fix the leak before the hard shifts took place, between the time i made the appt and saw my indi the hard shifts started and progressively got worse. Took abt 45 days to go from noticeable to troublesome.