I was wondering which year S-10 had the 3.73 positrac in it? And if you know, which RPO code was it. Or will I have to look and decifer if it is 3.73 posi. Thanks guys, I really need to get away from these 2.72 non-posi's.

 

I had an '87 with 3.73's behind a four cylinder four speed.

 

The RPO for 3.73's is GT4...the posi is G80.

You can also find these gear in Astro/Safari minivans. Some of the '87-'89 models also had 4.10's if you want a 7.5" ring gear.

 

sweet dude, didn't know that. Went to the junkyard today, and it was gay. They wanted alot for their stuff. So I have to keep looking, But thanks for the RPO codes, and Jay, those gears you have are stock, right? later guys.

 

if jay is talkin about an s-10 yeah they are stock equipment, i know of 2, 89 s-10's with 5 speed and 3.73 rears, another friend had, a 3.73 limited slip in his 84 2.8l blazer automatic, then he wrecked it, i wanted rearend insurance company said its totaled and wouldn't let us buy it back, another friend has a 89 4.3l blazer automatic, with 3.42 limited slip in it, both blazers were 4x4, the s-10's were not

 

Yes they were factory stock. My local junkyard wants between $125 and $200 for a complete rear, they won't sell internal parts though. Try car-part.com www.car-part.com they have parts from yards all over the country. And I have seen quite a few that sell used ring and pinions. You could also pick up an issue of petersen fourwheel and offroad magazine, in the little ads towards the back pages are companies that sell used gears.

 

I may be missing something here but is the S10 a bolt in deal b/c if not I don't know why you would want to go through all the trouble of setting up the Ring and Pinion in your housing when you could get the 3.73s in a stock Camaro or TA. The numbers are as follows:
1983 4JK 3.73 Posi
4JQ Same
4PQ Same
1984 6JQ Same
6PN Same
6PQ Same
1985 6JQ Same
6PQ
6PN
1986 8XX 3.70 Posi

That is it for anything over 3.70 but to me it would be much easier to swap brake to brake than try to be a rear end specialist, thats why it costs $1200 up to get them built.

 

Around here it's quite rare to find a third gen with 3.73 gears. No an s-10 rear is not a bolt in but the gears are, I have set up several rears myself without problems. S-10's with 3.73's are not very hard to find. And BTW it costs no where near $1200 to do this. You could get a ready to bolt in 9 inch or 12 bolt for that much.

 

I meant a shop where professionals do the job, you know. They charge about $1200 to do it right. Sure you can do your backyard swap and maybe it will hold up for a little while but inevitably it's gonna go. Especially if you're looking for 3.73 Posi, it isn't some grocery getting fuel economy car, you're gonna dog it. Lucky for me I'm in California where we have Junkyards stock full of these kind of things. So good Luck.

 

so are you trying to tell us that if we only pay $200 we are not getting a proper job done?

my $200 install/gear setup seems to be just fine, no whine, just pure enjoyment,

the only way it should cost $1200, to have a "pro" setup gears is if everything, including axles, and maybe even the housing is new

 

werd, if you bust your junkyard gears, you say **** it, put the old ones back in, or go buy the expensive gears, no tears shed.

 

Your an ignorant #@$% aren't you.
I have set up $800 worth of gears and posi four years ago in my brothers four wheel drive truck that regularly tows a boat on 800 mile trips, I've set up gears on every one of the three vehicles I drive some more than once because of ratio changes, they get driven 40 miles to the track and run hard, I have changed gears in friends cars as well. Never once had a failure and never once had a noisy set.
So just because you don't have the skills to do something right and you have to get someone else to do all your work for you doesn't mean we are all like that.

 

You guys might not want to swap in a 3.73/posi/disc axle. I did. (Besides the fact that the damn posi, which was really an Eaton Gov-lock in '84, blew up.) But- I spent over $600 rebuilding the thing- and 80% of that cost was for the damn brake system!! Yeah, I finally got working rear disc brakes, but $600? That's a new set of gears and installation.

 

why couldn't the average dumbass at home set up a gear set and have it last? i've done quite a few for drag racing, some cars ran in the 10s, carried the front end and all that, never a problem. guess it was sort of a professiosn install since i did get paid for most of them. i'll set them up all day long for 200 dollars, rear out of the car. all it takes isa few tools most people don't have, buy the tools and you're all set. guess i did have to make a couple since they can't be bought.

and guys even if someone is an ignorant *** on here you can't be pointing out what's in front of everyones nose. we all have our days right? so play nice while you at thirdgen.org.

 

Well I am not looking into disc brakes in the rear. I am not to interested in that, so all I will be doing is the posi and gear swap. I know they aint that hard, but I havent done them before. Anyways

 

I heard that summit sells a video for replacing ring and pinions in our cars. Does anybody know if this is true? Part numbers? Thanks
matt

 

The dollar amout means nothing. All that matters is the skill of the installer. I would much rather have a local circle track racer install the gears for cheap over a couple of beers in my backyard than pay a shop big dollars, not just because of the money--he would probable do a better job. I set mine up 5-6 years ago and it's never been apart since.

 

Will the gears out of an S-10 fit into a BW 9-bolt rear? I think there is a dead one out back my mother's place that I might have to check out. Where are the RPO codes on those things?

 

No, s-10's never came with 9 bolts.