I recently bought a 95 blazer s-10 lt. it has 256XXXmiles on it. it runs great and nothing is wrong. EXCEPT my wife was driving it and she said it just stopped all the sudden not the engine the truck itself. after getting it home doing only 5 mph for about 4 miles while it made a horrable grinding noise i came to determine it was the rear end. i took off the rear diff cover to see many chunks of the teeth in the bottom. My question is I cant seem to find what gear ratio or if its a 10 bolt or 12 or 14 . there is no metal tag and i checked all the stickers i could find on the blazer. oh it has 4wd and 4.3l vortec. how do i determine if its a 10 bolt or whatever and what was the stock gear ratio for that vechical. i plan on doing the work my self since i already took out all the guts to it. and mabey some one could mabey help a fellow blazer guy out and mabey sell a spare one to me if you have one laying around. for resonable price of course. thanks for reading my post

 

Unless someone was under there and got crazy, you most likely have a 10 bolt rear.

As far as the gear ratio, you'll have to look at your RPO codes and look for a G code.

GU6 is 3.42
GT4 is 3.73
G80 is the gov-loc

The above gear ratio codes are the most common, but post back if you have something different.

 

what is rpo codes

where do i find them

 

RPO stands for Regular Production Option for GM vehicles. They are basically a blueprint of what your vehicle came with. In Blazers they can be found in the glovebox and look like this:



This person has 3.73 gears and the G80 gov-loc as well as the ZR2 package.

 

thank you i found it i have the GT4 3:73 and G80. what exactly is gov loc

does any 1 have the part i need (rear diff)

 

Please take some time to look through the forum for your answers. Search will yield the results you're looking for and a quick browse through the classifieds will tell you if anyone has one for sale.

 

i am unableto get to the classifides since i just registered today but i need to find the parts i need how do i go aout doing that within this forum?

 

Gt1 axle rear, 2.56 ratio
GT2 axle rear, 2.29 ratio
GT4 axle rear, 3.73 ratio (dup with 5 x 1)
GT5 axle rear, 4.10 ratio (dup with gt8)
GT7 axle rear, 3.33 ratio
GT8 axle rear, 4.10 ratio (dup with gt5)
G80 is the "Eaton Locker" aka "G80 Locker". Many consider it the best differential made (arguablly). If I were you, I'd consider fixing it rather than replacing it. If you must replace it, try to get a good 3.73 G80. They are great.

Check out http://www.youtube.com/watch?v=AjymmXvBYsI

 

not really fixable when i drug it home the teeth that broke off reall chewed uo the guts of the whole thing . I am still looking fir a decient rear end but am not able to find one in my price range since i am unable to get on the classifides yet im just searching craigslist and other sites. i might have to wait a month or so till i get my taxes back unless some1 can help me out and point me in the rite dirrection. but thanks for the info, i will be looking fir the above reccomened rear end.

 

another question how do i measure how wide it is suppose to be from what point to point .the diff. if i did it rite i think i have 7.625"