GM 10-bolt R&P question

The more I research the GM 10-bolt axle, the less I seem to know. It almost seems disingenuous to say “10-bolt axle” when in reality it seems like a whole family of axles.

Rather than try to become an expert on the subject, I’ll just ask here: What other rings-and-pinion sets will interchange with an S10 axle? Specifically, I’m interested to know if the 2.56s from a ‘68 LeMans or the 2.73s from a ‘68 Camaro will replace the S10 pieces.

Probably not, but it doesn’t hurt to ask.

-Dave

 

im no expert but your s10 is probably a 7.5 like the 80 regals malibus monte carlos etc.68 camaro should be an 8.2 then i beleive 73 thru about 77 should be 8.5 rearends.also something i learned is your gm cars other than cheverolet used bolt in axles not c clip axles like chevy did. hope this helps.i was building a rearend for my car and it got very confussing

 

Some S-10's used an 8.5 ring and pinion but only the later models. The last 1997 I parted had the 7.5 as mentioned in the previous post. If you use a 2.56 gear and carrier you cannot swap higher numeric gears onto the carrier, you have to start with the 2.73 and up carrier to use 3.08, 3.42 , 3.73 etc.

 

I actually want the highway gears in the S10 axle (which I don't yet have). So it sounds like if I get an 8.5" S10 axle, I can swap the LeMans 2.56s, carrier and all, in? What year S10s use the 8.5"?

-Dave

 

or get the gears from a 78-80 GM A body like a malibu or regal or cutlass. Before they got overdrive transmissions, they had low numerical ratio gears. And the 78-up models used the 7.5 rearend.

Of course if you have an engine that makes some power, then go with the 8.5" rear....the 7.5 is ok with a 305, but iffy with a hopped up 350

 

GM used the 8.2 Ten Bolt rear ends until 1970 after that they switched to the 8.5 but the 8.2 is incredibly strong as is the 8.5. I have an 8.2 with a TH350 and run 3.73s its not bad on the highway, around 2800rpm @ 65mph. What year is the S10? 8.2 ring and pinion sets will NOT swap out with an 8.5. So if you have an 8.5 and are getting gears from a 68 LeMans with a 10 bolt (meaning an 8.2) it wont work.