The level should be at least at the "add" mark when the engine is running, in neutral, and cold. Generally, the fluid level will be quite a bit higher than the full mark when the engine is not running and cold. This is due to the converter draining back.
That is why it needs to be between the add & full marks in neutral when the trans fluid is hot after driving a mile or two.
Is the bottom of the pan wet from leaks? Transmissions get very unhappy when they run low on fluid. Revving it that high to get it to move is not good for it, for sure.
Not sure what you mean by temp sensor. The easiest thing is to simply add enough fluid to bring the level to the add mark when cold while the engine is running, in neutral, on a level surface. If it has issues moving at that point, then the trans likely needs to be torn down and rebuilt.
Almost every cold non-running one I've checked is at least well into the safe zone or above it.....
Well, what does it normally rev to pulling onto the trailer? That usually brings most close to the stall speed of the converter, some ramps/approaches are better/worse, so....chances are if You didn't smell anything "hot" or burnt, and the fluid smells normal, You're good.
