Gearbox surging

[Uberalles]

Need some help from the sifus.My 03 525i has started acting up. The gearbox has developed this funny habit.When I suddenly back off the throttle and the gearbox is in top gear, the car will start to softly, but quite noticeably slow down in small jerks....like someone is stepping very gently on the brake, then letting it go, then stepping on it again.....Only happens if the car is in top (5th) gear and coasting to a stop.The gearbox has already been flushed and checked.Anyone has any experience with this issue?

 

[rpmnut]

Could it be the lock up clutch actuator? Try plugging the car into an OBD unit. If the lockup clutch isn't disengaging properly, there should be error codes in the TCU.

 

[JFT63]

No such experience so far..rpmnut is right, diagnose your car for fault codes..happy hunting

 

[rpmnut]

Any updates on your gearbox issue, uberalles?