Did a search threw these forums about this problem I am having with a slip that occurs when the weather is hot outside, found only a little info about it and still have'nt resolved the problem.
I just bought a 2000 Ford F150 V8 5.4 liter Automatic, and during Hot weather with the AC on after driving for about 30 miles the truck will slips in first real Bad like it's in Neutral? Only happens in Hot weather tho, any idea on this type of problem? should i get a transmisson service? I read somewhere about some kind of TR Sensor might also be the problem? any help would be appreaciated thanks.

OMG mechanic can't evaluate this problem intill it happens so I have to drive it around when the weather hits 100 degrees and rush it to him what a bunch a BS :/

 

My '97 f150 with the 4r70w uses three temp sensors that control functions with the tranny.
1. Engine Coolant Temperature Sensor (ECT)
ECT is used to control the converter clutch
2. Air Charge Temperature Sensor (ACT)
ACT is used to control tranny EPC pressure (could cause harsh or soft shifts

3. Transmission Operating Temperature Sensor (TOT)(within the tranny) TOT is used to inhibit converter clutch engagement when cold etc.

The Air Conditioning clutch (ACC) also effects the EPC pressure due to the additional load on the engine.

There are so many variables, but these above all have input into your tranny indirectly, hence if you check that the first two sensors are within range and working correctly without any codes, you can concentrate on the tranny itself. Hope it helps.