[Nayook]

I have had a new F25 since 18th August this year.
The car has been driving normally ie like an automatic and once on the freeway I use to go to work the transmission locks up to a solid connection to the road. If I accelerate in auto or using manual in 7th or 8th gear at 70mph the engine picks up speed with the car and the engine revs increase with the car as if it were a manual. Normally the car does 1600rpm at 70 mph.

About every fifth day I drive the same route and the car is using a lot more revs for the same speed, if I accelerate the engine revs increase by about 500rpm without changing down, as if the power is going through a fluid connection and the lock up has not functioned. If I change to manual gear changes the lock up does not occur either. I can drive all the way to work (30 miles) without the transmission locking up. When this is happening the car does about 2100rpm at 70mph.

If I pull over and stop the engine then restart and drive off the transmission then operates as normal with a solid lock up through to the wheels.
I normally don't drive with auto stop start on. If I did the stop start would probably have prevented me from experiencing this.

Initial discussions with the dealer have highlighted that it could be the adaptive gearbox "learning" even though the car now has 7500 km on the clock.

Strange thing is, this only happens on the first drive of the day. Once I have stopped the engine it does not happen again that day.

Hopefully readers understand what I am describing but does anyone else have any ideas what is going on?