Rear axle

[bigballsbilly]

Ia posi carrier I purchased from another member here. The ring gear will not fit over the posi carrier. From the end of the ring gear opposite side it measures 7 and one half inches. It sounds to me like I have an incorrect 7.5 inch rear in my car. Any thoughts?

 

[bigballsbilly]

Also the ring gear has 41 teeth and the pinion gear has 17. That would be a 2.41, correct?

 

[v6turbo87]

Read the axle code off of the passenger side axle tube. It is stamped on the side of tube facing the front of the car.

 

[v6turbo87]

I am no expert but the shape of your rear end housing does not look right for an 8.5 either. The axle code will tell for sure.

 

[v6turbo87]

http://www.nationwideparts.com/differentials.htm

 

[dr_frankenstein]

That posi carrier is probably the larger 7.625 S10 unit. You will need the matching ring and pinion. But it will physically fit into the 7.5 housing. this is an excellent cheap upgrade.

 

[bigballsbilly]

Yeah its a 7.5". I guess my next post will be in the wanted ads for a rear.

 

[v6turbo87]

Huh? Never heard of a 7.75 GM rear end and how would it possibly be an upgrade over the correct 8.5 inch that the car is supposed to have?

 

[dr_frankenstein]

Huh? Never heard of a 7.75 GM rear end and how would it possibly be an upgrade over the correct 8.5 inch that the car is supposed to have?

it was the HD version of the 7.5 for the S10

its an upgrade for the 7.5 not the 8.5.

 

[pacecarta]

Also the ring gear has 41 teeth and the pinion gear has 17. That would be a 2.41, correct?

no need to check any codes thats a 7.5 , surprised you didnt notice the low gears which should have had the rpms really low at cruise but really poor for spool
if plans arent to push the car you could just look for a monte SS rear axle , or get a 7.5 eaton and gear set for it (around 800 with the install kit since youll be replacing the pinion)


i might be able to help on the 8.5 , just pulled a modded 87 gn rear drum to drum with the park cables .. 3.42 , stock posi , superior 28 axles, long studs , moser c-clip elims , s10 wheel cylinders

 

[dr_frankenstein]

Huh? Never heard of a 7.75 GM rear end and how would it possibly be an upgrade over the correct 8.5 inch that the car is supposed to have?

Im sorry Brother, I meant 7.625. you got me on that one!!

 

[bigballsbilly]

no need to check any codes thats a 7.5 , surprised you didnt notice the low gears which should have had the rpms really low at cruise but really poor for spool
if plans arent to push the car you could just look for a monte SS rear axle , or get a 7.5 eaton and gear set for it (around 800 with the install kit since youll be replacing the pinion)


i might be able to help on the 8.5 , just pulled a modded 87 gn rear drum to drum with the park cables .. 3.42 , stock posi , superior 28 axles, long studs , moser c-clip elims , s10 wheel cylinders

I knew there was something wrong when I got the car. It wpijld do a birn out, I had a pretty long thread that was "no power off the line". It had the wrong TC in it, I the stall was too low. When I put Dave Hudeks TC in it it woke the car up 100 pct. And now with the new TC I noticed its a peg lwg which led to me buying the posi from a member here. Which brings us up to date.

Where are you located?

 

[pacecarta]

couple miles west of etown raceway

 

[chris kirk]

Yeah its a 7.5". I guess my next post will be in the wanted ads for a rear.

I have a stock GN 8.5 " posi with new 3.42 put in with about a hundred miles on it. Has the drum brakes, too. If you are interested let me know. Had new gears put in because when I bought the car it had 3.73 in it and I hated the way it drove. I took the rear out a few weeks ago because I bought a 9" Ford from Moser.

 

[bigballsbilly]

Pacecarta hooked me up with a real nice rear. He delivered it to me today and I put it in. Works perdectly. Thanks!

 

[John Larkin]

Isn't it ridiculous that someone cannibalizes a good car and replaces those parts with sub-par pieces, then sells it to an unsuspecting buyer who down the road has to diagnose and undo it all? All that mayhem for a couple of bucks. Sometimes people just amaze me.

 

[bigballsbilly]

Yep. Crazy. I'm guessing the PO f'ed up the rear and got sticker shock when be found out how much its gonna cost to fix it. So they had the cheapest thing done to get the car on the road.