This is my first post here,
I put a good amount of time in prior to posting here with using the forum search, but I had no luck in finding anything.
I have been having

I believe I may have an electric issue which is causing the gear box to slip in and out of gear when travelling around 90-100 km/h. It usually happens on flat roads and with no driver input at all. It is also happening at 60km too. Only in the upper gears.
I have recently had over 1700$ worth done to the gear box (torque converter + engine mount replacements), and the crowd that did it doesn't seem to want to know about the issue that is still occurring.
I suspect it to be a solenoid or a sensor unit.
The unfortunate situation I am in, is that I am in Perth, Western Australia. and the Nissan dealerships will not touch grey imports and these r50 terrano are super rare, even though they are much sort after here. So the Australian pathfinder forums, haven't been much of a solution finder.
I have also hooked up ecutalk (no error codes) and I have collected data. I am happy to post photos.
I was considering replacing common sensors, (TPS & crankshaft position sensor).
As when I first got the car, my mechanic was going on about these water marks on the engine (water pump leak) and the silly me, thought I would give it a clean (over 9months ago) to get rid of the water stains to see if there was an actual leak, if they returned (they never did).
I was thinking moisture maybe a cause. But I cant seem to find a TPS.
Has anyone got any possible ideas? or perhaps the QD32eti R50 terrano service manual in English?
Regards
Andrew