4th gen rear or 9 bolt
Thread Starter
Member
Joined: Oct 2006
Posts: 125
Likes: 1
From: Michigan
Car: 85 Iroc-Z
Engine: 350 4bbl
Transmission: T-5
4th gen rear or 9 bolt
well, i have access to either a 4th gen rear, or a 9 bolt rear, and i'm trying to decide which one to go with, if I use the 9 bolt it needs new calipers and disks (could I use the 4th gen ones?) and if I go 4th gen I need new rims and axle shafts. what do you guys think?
Joined: Jun 2004
Posts: 918
Likes: 31
From: Las Vegas
Car: '88 Trans Am
Engine: 5.7L TPI
Transmission: Slushbox
Axle/Gears: 3.27
Re: 4th gen rear or 9 bolt
the aussie 9bolt is a better choice!
it is stronger than a 10 bolt,been through the debate 100 x's the only true drawback is the available gears for the 9 bolt 2.77,3.27,3.45 easy to get now 3.70 and 4.10 will take some hunting TPIS has the 3.70 but its like 400.00.
if you are ok with the avail. gear options you are good to go.
it is stronger than a 10 bolt,been through the debate 100 x's the only true drawback is the available gears for the 9 bolt 2.77,3.27,3.45 easy to get now 3.70 and 4.10 will take some hunting TPIS has the 3.70 but its like 400.00.
if you are ok with the avail. gear options you are good to go.
Junior Member
Joined: May 2007
Posts: 96
Likes: 0
Car: 1987 Iroc-z
Engine: 305 TPI
Transmission: Modified T-5 World class
Axle/Gears: 9 bolt borg-warner 3.45
Re: 4th gen rear or 9 bolt
I have the 9 bolt and love it. However I've been told that the calipers are expensive because of the parking brakes in them.
Thread Starter
Member
Joined: Oct 2006
Posts: 125
Likes: 1
From: Michigan
Car: 85 Iroc-Z
Engine: 350 4bbl
Transmission: T-5
Re: 4th gen rear or 9 bolt
seeing as i already have this thread, how do i know which gear it is. the rear may be original to the car, but it looks like the doors and center console arent.
Supreme Member

Joined: Jul 2003
Posts: 2,779
Likes: 2
From: any clime or place...
Car: 1987 Camaro SC, 1999 Z28
Engine: GMPP 350HO, LS1
Transmission: Built 700r4/EDGE 3200, T56
Axle/Gears: 3.42 Eaton 7.625, 3.42 Zexel Torsen
Re: 4th gen rear or 9 bolt
9 bolt is stronger, but if its too worn out, i think i'd go 4th gen. however i hear eaton is gonna make a 9 bolt posi, so then again...
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