Trans Leak when hot - I have a 2004 Chevy silverado 6.0, 2500 HD 4wd. I was pulling my camp trailer up a long steep grade in tow haul mode, ...

I have a 2004 Chevy silverado 6.0, 2500 HD 4wd. I was pulling my camp trailer up a long steep grade in tow haul mode, and the trans temp rose to just below the red. I looked in my mirror, and saw smoke. I pulled over and got under the truck, and saw a little trans fluid dripping on the exhaust pipe. It looks like it is coming from the fitting where the trans dip stick enters into the trans housing. Have you seen this before? Is there any type of temp/pressure relief valve?

You should have a vent fitting at the top of the transmission. It may have a short hose attached to it and the other end connected to the floorboard. Your transmission was exposed to some high tempertures and it probably is a good idea to change the fluid.

I agree you need to change the fluid. Also check for cluch matieral in pan. That high of heat i think you have some other problem going on. My truck trans temp has never got close to the red (210 highest). I just towed over Mt hood in 90+ dregree heat for 160 + miles. Just something to think about hate to see you broke down.