[wickemt]

Hey all. Long time lurker, first time poster.

New BMW owner of an old (2007) BMW x3 3.0 with the 6 speed manual. I got a sweet deal on it because it needed a transfer case. The prior owner had already done the actuator gear and it didn't fix the problem, I did some forum research and figured the work was within my scope of competence.

December 2021, ordered a rebuilt transfer case from TC5BMW and did the swap. Took 3 days (a couple of snapped bolts) but all was well. Reset transfer case adaptations, went for a drive. Lights went off, and then came back - code said right rear wheel speed sensor. Replaced that sensor, same problem - no data coming from the sensor (rear right reading 0-2 mph while the rest read accurate). Next step will be to clean the ring inside the hub with brake cleaner and a screwdriver; if that doesn't work I'll swap the ring or the hub.

My new problem is a real head scratcher. I'm getting a jerking/bucking while decelerating, but ONLY when in 1st, 2nd, or 3rd gear, and ONLY when in gear. If I clutch in, everything is fine. If I hit the gas, everything is fine. If I'm in 4, 5, or 6, everything is fine. But if I'm in gear and not on the gas, the car bounces/bucks/jerks noticeably.

I can't figure it out. Some of the relevant posts talk about transfer case fluid, but I put in the fancy BMW fluid when I did the transfer case swap. Wondering if anyone has any ideas, before I take it to the local indie shop and let them bend me over the counter.

[wickemt]

Update, replaced transmission fluid, life is good. In case anyone has similar issues.