RICHRAD

The stock rearend in my Trans Am is a 10-bolt. Am I safe to say I have a 7.5 ring and pinion with 26 spline axles. Also If I change my open to a posi does series 2 or 3 matter anymore.

GMTech

What year T/A is it? I think in '85 GM went from the 7.5 to 7.65. Also, if its pre '89 then its a 26 spline.

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RICHRAD

ooops !! Tried to get it up there too fast I guess. It's an 86.

RICHRAD

aw man, I think I've been this route before .Just trying to figure out what I think I might have as a rear now. Should have known, If there's anything that draws a blank on this website , it's REARENDS!!

RICHRAD

Excuse me, I gotta grip now! One more question though. I thinking of purchasing a GM 7.5 posi w/26 spline and 3.42s. Will this go in my 10 bolt housing if it is presently a 7.625 ?

82camaro

the only thing different is the ring and pinion. You case will work just fine.


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82 camaro--original steering wheel, brake/gas pedals, seats--everything else modified
82camaro

RICHRAD

Thanks GMTech, 82camaro . Bought this afore mentioned unit tonight on the web.Hope the thing installs okay. Do you think I'll notice a considerable difference over my 2.73 open rear? Even with a stock lg4?

RICHRAD

Anyone done this along with lg4 mods??

RB83L69

One of my little brothers used to have one, he went from a 3.23 to a 3.73 from a L69 car. Made a HUGE improvement but it still was far slower than my L69.

If you have a 2.73 in there now and the posi carrier is a 3-series, it will not work. The flange for the ring gear will be about ¼" too close to the pinion. If however it is a 3-series (more likely) you can stick a set of 3.42s in there. Your axles are 26 spline, so as long as the carrier is 26 spline (more than likely it is) you'll be OK.

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RICHRAD

I think I have a 2 series right now with the 2.73. I thought that ( series ) didn't matter as long as the 7.5 posi unit has a matching ring and pinion. Two and three series all fit the same 10 bolt housing don't they?

JoelOl75

Yes, the carriers are interchangable. Just make sure the ring&pinon match the carrier. Some aftermarket gears are matchined thicker so you can bolt a 3 series type gear on a 2 series carrier; but with stock gears you have to get a matching one.




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'88 Camaro RS 2.8L
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