Gearbox fine when cold. After about 25 mile drive it sticks in some gears, revs up between changing gear. Got oil changed. No difference. 2007 model. 79,000 miles. Can anyone help? Thanks.
Assuming that you've checked that the oil was of the correct specifications, and that it's at the correct level, there are three main options.
I have been having a similar problem especially when decelerating to islands and then accelerating away, the gear box has hesitated and not changed down before accelerating.
I have only done 36,000 miles, so I don't beleive it is the gearbox at all I beleive its the ECU not getting the right torque settings for a particular shift pattern. Last week stopped off at local post office to pick up a parcel and when restarting the car the engine light came on and in limp mode fopr 10 minutes. I stopped the car and restarted and all appeared ok but for the engine light which stayed on for 2 days.
After the initial problem the car has totally changed its driving performance, no hesitation or sticking in gears at all, turbo like acceleration throughout rev range and almost inpercetable changes.
I believe its either a small air leak in the boost line at the front of the engine, a dirty EGR valve or a clogged boost valve near the EGR. Try cleaning with carb cleaner before any drastic gearbox action.