Engine revs rise at odd times - gearbox?

[treeman]

Originally Posted by X53Jay4.8is

So the engine revs higher while the vehicle is in motion going up hill but there is no speed increase? If so it sounds like s slippage of some kind. What kind of maintenance have you performed on the X5 in the 12 years that you have had it? By the way is your X a 6 cylinder or 8 cylinder model?

Yes, no speed increase. It does feel like something is slipping.
The vehicle has been serviced exactly according to the requirements by my BMW dealer - all dealer serviced. In the 12 years all its had done is a fuel injector replaced and the middle fuel pump replaced. It is due an inspection 1 next month.
It is a deisel 6 cyclinder 3.0