1990 454 ss rearend compatibility

[Daniel J. Sheets]

I have a 1990 454ss it has a 14 bolt rearend and was told 373 gears but it does not have positraction it is 5 lug. I would like it to have positraction. My thinking i would take the internals out of another rearend and put it in mine to get 373 gears with positraction. While looking at different rear ends I have come across a 88 3/4 ton truck rearend. It has 373 and posi and is a 14 bolt rearend but it has 8 lug axles. Would I be able to take the gears out of this rearend and put it in mine? also would like to know what other rear ends would be compatible, would it also have to be a 2wd?

[CamGTP]

You are better off buying a posi unit that is made for your rear end. If your gears are in good condition just re-use them along with new bearings.

 

I wouldn't want a stock GM style locker. Get a real posi unit from someone like Eaton.

[davester]

... of course, GM's locker, the G80, is a real locker made by Eaton....

[CamGTP]

The G80 is garbage if you want to thrash it.

[91 Shortbed Chevy]

I thought all 1990 454ss trucks came with 4:10 gears and the G80 locking differential. I thought they went to the 3:73 gears in 1991 when they offered the 4-speed automatic.