S-10 Read End Questions

hey guys

I've been trying to find specs and info on the stock S-10 rear ends. Basically, if I'm building a car do I want to trade for something different? I'm thinking of trading up to a ford 9 inch, but I wanted to do the research first to see if I should just keep the S-10 rear end.

Thanks

 

What are you putting it under and how wide a rear end do you need??????

 

S10 Rear Axle Info

There's 3 widths of S10 rearends.
Doesn't matter if it's a Blazer or a truck, they share.

WMS to WMS width
55" = 2WD
59" = 4WD
63" = ZR2 off road option

7.5 vs 8.5 school
8.5 rearends are not common.
Look in 2nd generation S10's that originaly had a 5 speed trans.
Disc brakes were an option in '95 and became standard about '99.

7.5" rear end.
The axle tubes are straight where they enter the pumpkin
The rear end cover has a more squareish shape

8.5".
The housing cover is almost completely round
There's a bulge in the axle tube just before it goes into the pumpkin

Another bit of S10 axle info:
Look in the glovebox for the production "data plate" sticker.
It has the RPO codes to determine ratios and diff type.

GU2 2:73 ratio
GU4 3:08 ratio
GU5 3:23 ratio
GU6 3:42 ratio
GT4 3:73 ratio
GT5 4:10 ratio

GQ1 Open Differential Rear Axle
G80 Positraction/Locking Rear Axle

example:
4:10 posi rear would have two RPO's.
GT5 & G80

Exceptions to the rules:
If you find only a GQ1 on the data plate and no
"GU" or "GT" codes, then it's an open diff "standard ratio" of 3:08.

If there's no "G80" or "GQ1" it's an open diff.

 

I never saw an S10 with an 8.5" axle. They all had 7.5" or 7.625" axles, to my knowledge. (I think the ZR2 4x4 S10 had 8.5" axles in that suspension package) The 7.5" was known as a weak axle, but the 7.625 was pretty strong and used in the F-body, S10, Astro, etc. after about 1988, I guess. The '93 & up units are plentiful and strong.

I used to order the Auburn limited slip carriers from Lingenfelter Performance for $75. They were new OE take-outs that LP was replacing with a better unit.

 

need more details on what you are building.

 

Look for the 8.5 ring gear rearends in 2nd generation 2WD V6 5 speed Blazers. If it has a New Venture trans, it probably has the 8.5 rearend. They're more easily found in Blazers or Jimmys than pickups. I've bought/sold a few but never personally seen one in a pickup. I know they came in non-ZR2 pickups because my friend has one he installed in his 1st Gen V8 Blazer.

 

An old thread with some good information. Can anyone confirm that the spring-perch distance on an S10 rear is 38.5" center-to-center? Thanks.