Rear differential question
 

I need to know what year chevy truck would have had a posi differential in it? 5 lug with 373 gears any one know?

Re: Rear differential question
 

My 68 has the 373 posi from the factory.
Oops,mine is 6 lug!
Mike.:chevy:

Re: Rear differential question
 

i know my step dads 73 suburban had posi not sure on the gears though, but i know our 89 sub had 3.73 posi i dont know if that helps you at all but i figured i would give my 2 cents

Re: Rear differential question
 

There isn't any specific year or model of truck that will definitely have 3.73's and a posi. It just depends on what options a truck was ordered with. It's just a matter of searching and either checking build code stampings or pulling covers.

Re: Rear differential question
 

5 lugs were usually 2wd trucks 71 and newer. Look for factory towing package as most of them were 373.