I have a 2001 1500 V6 5-Speed (2wd, 9.25 rear end) that I am going to be doing a gear swap with from 3.55s to 4.88s as I'm doing a lift with 35" tires. I use this truck for towing as well. I will also be running a Lockright locker.


Would 85W/140 synthetic gear oil be too thick? Would 75W/140 be better?


This truck stays mostly in Arizona, or at least the west, so during the summer, it sees temps over 100 on a constant basis, and during the winter, nothing colder than about 30 overnight, but regularly in the 70s.

Thanks!

 

Run the heavier and if you can, get one of the covers that holds more fluid.