What gear

[Bruce Allen]

Which gear oil should I use?

 

[Diesel Nut]

I like Amsoil, but you can use whatever brand you want. You need to run a synthetic, and unless you are towing super super heavy 75w-90 will do perfectly. You'll get better fuel mileage with the 75w-90 than the 75w-140 also.

One other thing if you tow is get a Mag-Hytec rear end cover. They add 4 quarts to the rear end and help it run cooler.



Rear end holds 4 quarts.

 

[Nate]

I put Valvoline 80w90 when I change the diff oil on vehicles. It's about $35 for a 5 gallon bucket.

 

[Bruce Allen]

Im in Colorado so the tempertures are extreme for highs and lows.