I have a 2003, automatic, 3500 with a single wheel in the rear, and four wheel drive. I was hauling 3000lbs of rock and pulling a dump trailer loaded with a tractor up a 15% grade yesterday. The temp gauge raised up above the 200 mark where it normally hovers around. Near the top of the hill I turned around so I could make it into my driveway. When I stopped along the shoulder of the roadway the front of the truck was facing down the hill. I noticed ATF fluid leaking from the inspection plate, which was a stream when the engine was revved. I read some threads about the cooling line leaking and it was not that. I also looked at the fluid and could tell it was ATF. The truck cooled for a bit and I started it again before I drove it 150’ or so with no leaks like before. I pulled the inspection plate and it was not leaking like before. Has anyone encountered this problem previously or does anyone have any thoughts on the potential cause?

 

Thats not to unusual for your circulstances. There is a case vent on the pump behind the TC. With the load you were pulling and the grade, guessing the TC was not locked either, it just heated and churned the fluid up really well. When you parked nose down it all ran to the front of the trans and some out the vent.

After you let it cool down and the fluid de-aerate it doesn't leak any more. The sump of an automatic is open, extreme angles and heavy use will expamd and aerate the fluid a lot. As long as quit leaking when it cooled its probably fine. Just check your fluid level and see where it is.