Author Topic: Rear axle gear change  (Read 1983 times)

Offline Plasticfan

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Rear axle gear change
« on: February 20, 2017, 03:41:11 PM »
Want to swap out my 2.73 gears for 3.42.  Will the 3.42 fit in my 2.73 housing?  Are all the pinions 30 spline?

TIA, Don

Offline Captkaos

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Re: Rear axle gear change
« Reply #1 on: February 20, 2017, 09:01:11 PM »
what year and size is your axle?  12bolt or 10bolt.
All 10 bolts have a 30 spline pinion.
It is the carrier that you want more spline count.  Only the later model 1989-1991 10 bolts got 30 spline axle.
Carrier break on a 10 bolt is 2.56 / 2.73

12bolt truck axles all have 30 spline.
Carrier break is 2.73 / 2.76 / 3.42 / 3.73

Offline Plasticfan

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Re: Rear axle gear change
« Reply #2 on: February 20, 2017, 09:12:11 PM »
what year and size is your axle?  12bolt or 10bolt.
All 10 bolts have a 30 spline pinion.
It is the carrier that you want more spline count.  Only the later model 1989-1991 10 bolts got 30 spline axle.
Carrier break on a 10 bolt is 2.56 / 2.73

12bolt truck axles all have 30 spline.
Carrier break is 2.73 / 2.76 / 3.42 / 3.73

Mine is a 10 bolt, 8.5" ring gear.  Looks like I'm good to go then. 
Thanks, Don