I pull a 22k trailer with 3.54 gears and run amsoil lube. Do i need to do anything to make this live, or is it good in stock form?

 

Check with your Amsoil dealer , most lubes require a fiction modifier for the locking diff .

 

After a long pull, you could put your hand on the cover and see whether it is really hot. If so, an aftermarket cover with more capacity and better cooling would be good. It is going to be warm but it shouldn't be too hot to touch.

 

Honestly I think it would be fine... I've done the hand test after towing very heavy a couple of times and its always been fine... If you are worried I'd suggest a magtek pan, let you put an extra qt of oil in and has some cooling fins...

 

I have the Mag-Hytec pan and have never had a problem, I believe Amsoil already has friction modifier in it, but check the bottle. The D80 is so strong you should never have a problem with it, most guys who sled pull don't bother modifying them...occasionally stronger shafts, but for towing you'll never need them, the full floaters stock are more than adequate.