The Stovebolt Site Forums The Shop Area Engine Shop 56 GMC axles/od's?

Help is a click away!

VEHICLE
INFORMATION
KITS

at the

GM Heritage Center
All the details are here.

Searching the Site - a click away

New here ??? Where to start?

Click on image for the lowdown.

====

Who's Online Now

5 members (rfs56trk, Gib70, Lightholder's Dad, Gray_Ghost, 1 invisible), 134 guests, and 1 robot.

Key: Admin, Global Mod, Mod

Forum Statistics

Forums66

Topics128,080

Posts1,056,060

Members48,433

Most Online14,466
Apr 26th, 2026

Step-by-step instructions for pictures in the forums

Brad Allen's photos

AD Chevy Trucks

Pictures galore

Over 6,000 pictures

Brad Allen has an awesome collection of Chevrolet factory pictures that he has set up from film strips.

Check them out!

Lots of work on Brad's part ... pure enjoyment (and references) for you!

Big Thanks!

THANKS!

For helping keep this great
old truck web site
on the Internet for

over 30 years!

and not clogged down
with Ads!

Again, thanks!

Print Thread

56 GMC axles/od's? #47814 07/18/2005 7:57 PM
Joined: Jul 2005 Posts: 3 PHX AZ B Bob K Junior Member
Bob K Junior Member B Joined: Jul 2005 Posts: 3 PHX AZ	I have a 56 GMC with Hydramatic and the Pontiac v8. I understand the rear end ratio is 3.9 to one. It looks like the diff is either a GM ho33, or a Spicer 45. How can I tell the difference? So far I can see these options for a better road ratio: change the gears in the diff, put in a o/d auto transmission, chamnge the diff, or add a gearvendors o/d. Anyone have a suggestion of an axle down abt 3.31 or so? Thanks. Bob KNOTTS

Entire Thread
Subject	Posted By	Posted
56 GMC axles/od's?	Bob K	07/18/2005 7:57 PM
Re: 56 GMC axles/od's?	Flxible	07/18/2005 8:46 PM
Re: 56 GMC axles/od's?	Wrenchbender Ret.	07/18/2005 10:23 PM

Moderated by Phak1, Woogeroo

Hop To

Link Copied to Clipboard