Nissan Repair: X Trail automatic transmission problem, automatic transmission problem, fancy accessories

Question
I am in Kenya,  I have a 2002 X Trail 2.5 litre petrol automatic transmission.  After 2-3 hours of driving in hot city conditions, the automatic transmission suddenly goes into high revs, the car hardly moves, its like moving into neutral.  The ATF fluid level is fine, we have changed it since the problem developed, still the problem is there.  If you shut down engine, and let it cool down, it is fine after about 15 minutes.  In the cool of the morning it is fine.  The problem develops only after a couple of hours on the road, especially hot conditions.  Could this be a problem in the ATF temperature sensor?  What can be done about it?  Here in Africa we dont have access to fancy accessories or cooling mods.

Thanks
Richard

Answer
Richard,

I would find a transmission cooler.  The biggest you could find and install it.  It is not a fancy mod.  Just go to a wrecking yard and find a large truck and source a cooler off of it and then run it in series with your stock cooler.  Feel the lines after yours is hot.  The cooler of the two coming out of the radiator is the line/hose you want to cut to run the cooler in series with.  You will be most happy since this modification is a great solution to your problem.