I have an 09 Sport, I drove locally for 20 kms all city, got home and climbed under truck to check exhaust when I noticed the rear diff was pretty warm, is this normal?

 

Check the fluid level, if it's at the correct level I wouldn't be to concerned.

 

all in good fun my friend

 

Yes it is normal, just like your tranny, gears get hot...lower gears even hotter. Put a 5.13 gear in there and you could prob cook an egg on your cover, lol!

 

This makes a good case for larger than stock and possibly finned differential cover like mag hytec.Stock gear oil capacity is 4.7 pints. Mag hytec cover is 3.5 qts.I am also a believer in amsoil sever gear 75-140.

 

Normal operating temp is about 120-130 degrees, can get up to about 150 on a hot day. 150 is about 3 seconds of laying your hand on the pumpkin before you gotta pull it off and yell "ouch", so if you can do that, you are fine...