Newby question, where do I find out what my rear dif ratio is? [Archive] - Diesel Place : Chevrolet and GMC Diesel Truck Forums

: Newby question, where do I find out what my rear dif ratio is?


rmay635703
03-25-2004, 12:37 PM
Newby question, where do I find out what my rear dif ratio is? Is it located on the truck somewhere?

I would like to see what the rear dif ratio is on my 2 old 6.2 diesel subs. As I am curious as to why my newer 4 speed truck gets about the same mileage as my old 3 speed 82 sub.

Thanx
Ryan

GMC2500HD
03-25-2004, 01:01 PM
If you look in the glove box there should be a label with tons of numbers and letters on it. You will need to look in the owners manual and find the code for the 4.10 and 3.73 rear ends and see which one matches. I think that should work, also depends on what year your truck is. Easier solution, call the dealer and have them do a VIN pull and that will tell you what is all in your truck.

alky
03-26-2004, 12:19 AM
Look for a tag on the rear end. Some of them have a little aluminum tag and it says what the ratio is.