questions on GM 9 bolt rear

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Mar 25, 2010 | 06:13 AM

IROC_Z89

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From: Queens,NY

Car: 89 IROC-Z

Engine: 350 tpi

Transmission: 700r4

questions on GM 9 bolt rear

summitracing.com shows no rebuild or gear sets for the 9 bolt. I have a 9 bolt with 2:77s but would like to put in 3:73s soon. Is it possible to change gears in the 9 bolt and if so where can i find the sets? Thanks

Mar 25, 2010 | 06:38 AM

JamesC

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From: Lawrence, KS

Car: Met. Silver 85 IROC/Sold

Engine: 350 HO Deluxe (350ci/330hp)

Transmission: T-5 (Non-WC)

Axle/Gears: Limited Slip 3.23's

Re: questions on GM 9 bolt rear

Quote:

Originally Posted by IROC_Z89

Is it possible to change gears in the 9 bolt and if so where can i find the sets?

https://www.thirdgen.org/forums/afte...er-9-bolt.html

JamesC

Mar 25, 2010 | 09:07 AM

big gear head

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Re: questions on GM 9 bolt rear

You can't put 3.73 gears in a 9 bolt with 2.77 gears. The 2.77 uses a 2 series differential and you need a 3 series for the 3.73 gears. You will need the differetnial from a rear end with 3.27 gears to install the 3.73. You can buy the differential new, but it is expensive.