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Discussion Starter · #1 ·
Does anyone on here know the spline cound of the axles on a 7.5 rear out of a 94 caprice? I have a set of gears and posi for a 7.5 axle but not sure if the spline count matches up. I know it has whatever the older IROCs and S10s r but not sure if they upgraded the 7.5 in the b body or not. I know the late 90's to 02 have more spli camaro's and firebirds have more than the 3rd gens but not sure if that applies to the caprices. Thanks for the help guys.

Brent
 

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It would have been foolish if they didn't upgrade them from the 26 spline, to the 28 spline when the Caprice sedan got much heavier for 91. However, a posi in a 7.5", in a Caprice... That is a disaster just waiting to happen. There is a reason they never put a positraction in a 7.5" in a 91-96 Caprice sedan.
 

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With an L99 for foul weather driving a posi 7.5" might be OK, but a stock LT1 has been shown to chew them up and spit them out in chunks.

I would sell the bits you have and buy a junkyard 8.5" and driveshaft.

IMO the 7.5" axle was a bid to get .01 more mpg from the L99 cars to bring up CAFE numbers. It should not have been used.
 

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Discussion Starter · #4 ·
It's only a stock motor with a little intake work and duals. only reason I was wondering is cause I have the parts laying around and don't have the money at the moment for the 8.5 with disc and posi. The 4.3 really isn't that bad but the 2.73's kill whatever potential that the motor has. I have a set of 3.73's with a posi laying around in my garage and figured if I could use them for now to provide a little more get up and go then I would. not too concerned with blowing it up cause as I said its a stock 4.3.
Brent
 

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Years ago I counted it but I forget what the count was. I know the guy I sold them too tried to put them in a car with a lower spline count but I don't remember what his car was.

My car came with the 4.3l and yeah it was OK but did NOT do much for fuel economy under most conditions vs. an LT1.

I understand what you are doing, and can't really argue other than to say you will need to save some money for reprogramming.

Far as the disc 8.5" thing, the discs in stock form do not work as well in daily driving as the drums because GM put a drum proportioning valve on them, and it is the front of these cars that needs a brake upgrade. So don't go assuming the discs are a huge upgrade.
 

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Discussion Starter · #6 ·
I know it's not gonna b a huge improvement, I plan upgrading the fronts and wouldn't like the look with out discs in the back 4 one and I will upgrade the rear ones too. Counted the splines on the posi unit, it's 26, from what I've read and little detective work I've done i think they r 28 in the caprice. oh well. Guess I'll jus save them for my planned S10 I'm gonna build eventually.
Brent
 
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