How hot do differentials/ pumpkins get?

I wouldn't worry about that at all. If you were up over 200-210°F I'd start to take notice. Once oil approaches 250°F you're getting into territory that starts to damage parts and cook the oil.

 

Mine usually hover around 160-170f when im pulling a full 80K and it is not unusual to see it spike as high as 200 on a long mountain pull at 80k either. Like cat said unless it stays around 200 dont worry about it.

 

Just curious…. Were both diffs the same temp…?

asking for a friend

 

Front will always run hotter.

 

I wouldn’t worry about 170. We used to peg both rear ends into the red dropping down Whitebird at 105k in the summer.

 

We change diff oil every 500 k and they last well over 1.5 million running 35% mountains 65% prairies.. Boss rarely sells a truck he maintains them extremely well instead so some have major miles on them. PS because we run mountains a lot he makes sure every truck has a manual fan switch which helps tremendously on tough pulls .

 

The hotter it is outside, the hotter your rears will run. The front will always run hotter than the rear. Weight and terrain will also effect the temperature. 168° is normal.