X4 30d - Car won't accelerate cleanly in lower gears. it feels like slippage n slight shudder as the revs increase. not so bad when taking it easy... anyone have the same issue? Cheers

Chopper - sorry about that.

There are discussion right now on X3 forum about similar problem, but more related to turning.

One proposed solution is flushing transfer case. BMW say transfer case is sealed for life, but there are some -("many ?") which have resolved problem with flush.

well BMW have now checked the car and can't figure it out. booked in next week for 3 days and hopefully they will figure it out. thank God for warranty

All sorted. Transfer case and diff oil changed. All is good again

This is - a bit - surprising, since BMW says transfer case is "sealed for life", but , again, other people have testified good result with changing oil/flushing.

Any comment on status of oil? - infested with water or whisky?

Chopper45 wrote

X4 30d - Car won't accelerate cleanly in lower gears. it feels like slippage n slight shudder as the revs increase. not so bad when taking it easy... anyone have the same issue? Cheers

I had exactly the same issue. No codes and no CEL. Opening up the actuator motor and black gear is good. Replaced the transfer case drive chain, and problem fixed. When accelerated from stop, it jumped teeth due to stretched chain (dirty oil caused the chain to stretched). I spent less than $100 for part and dealer wanted $3,000.

https://www.ebay.com/itm/191033934838

There really is no such thing as lifetime oil. I always change mine around 80,000 miles. My X4 has 117,000 miles with no issues.

I changed mine around 50k+ miles and the transfer case fluid was disgusting as was the front diff oil and zf trans oil. Rear diff oil looked like new. I don't know what a reasonable interval is for the transfer case, anything but never.