The Stovebolt.com Forums Home | Tech Tips | Gallery | FAQ | Events | Features | Search
Help is a click away!

VEHICLE
INFORMATION
KITS


at the

GM Heritage Center
All the details are here.

Searching the Site - a click away
click here to search
New here ??? Where to start?
Click on image for the lowdown. Where do I go around here?
====
Who's Online Now
1 members (UtahYork), 128 guests, and 4 robots.
Key: Admin, Global Mod, Mod
Forum Statistics
Forums66
Topics128,186
Posts1,057,318
Members48,469
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!

Previous Thread
Next Thread
Print Thread
Joined: Oct 2010
Posts: 1,232
L
'Bolter
'Bolter
L Offline
Joined: Oct 2010
Posts: 1,232
How can I easily calculate the gear ratio in a torque tube rear end? Can't count turn of the driveshaft. Don't want to pull the plugs, tranny in 4th (1:1), push truck, count engine turns and wheel turns.

I believe that my '54 3100 has a '50 rear end. Date code on housing: H E1 21 = 1950 3100 Regular Rear Axle, Detroit plant, Jan 21, 1950.

EDIT: I JUST SAW THE GHOST OF A "2" AT THE END OF THE DATE CODE IN THE PHOTO. WHAT DO YOU THINK IT MEANS? NEVER NOTICED IT BEFORE.

1950 ratio is 4.11:1, 1954 ratio is 3.90:1. The diff is quiet and causes no problems. The speedo seems to mirror the speed shown on my GPS. I don't push it, but I know that it will run over 50mph.

> Rear axle cover
> Rear axle date code
> 1950 GM Resto Pack serial numbers

I have a buddy who is hot rodding his '54 and will have his rear end available. I may buy it. Anything to look out for?

Thanks for your help,

Last edited by LonnieC; 06/30/2012 4:02 PM. Reason: "2" at end of date code

- Lonnie
My '54 3104
Photos that I have shared on Stovebolt via PhotoBucket are no longer available. Please contact me if you want a photo from an old post.
lonniecook [at] aol [dot] com. I sold my '54 3104 12/12/2017, but I still visit Stovebolt.

OLD STUFF ... houses, furniture, cars, wine ... I love it all
Joined: Aug 2004
Posts: 1,418
ODSS Lawman
ODSS Lawman
Joined: Aug 2004
Posts: 1,418
If its a 50 1/2 ton, it is a 4:11 gear. Going from 4:11 to 3:90 is not worth the trouble in my opinion. Too small of a change.

If you install Patrick's 3:55 set, that will make your truck cruise at 70 all day long....

To confirm what you have you will need to pull the diff cover and count teeth or check the stamping on the pinion gear itself..


SWEET
Sergeant At Arms: Old Dominion Stovebolt Society
BUNS?!?!?!Where we're going, we don't need no buns.....
1950 GMC 450
1951 Chevy 1/2-Ton
The GreenMachine
In the Stovebolt Gallery
Joined: Sep 2001
Posts: 29,270
Bubba - Curmudgeon
Bubba - Curmudgeon
Joined: Sep 2001
Posts: 29,270
HE 12 12

HE = 1950 regular 3100 rear end
12 = December
12 = 12th

?

I agree with SWEET, unless you want a correct-date rear end, and your '50 rear end is OK, I'd only take the 54 rear end if I had a place to store it and if it was a freebie.

Joined: Oct 2010
Posts: 1,232
L
'Bolter
'Bolter
L Offline
Joined: Oct 2010
Posts: 1,232
Thanks guys. Guess you're right. Everything works well and it looks like I would pick up less than 3mph with a 3.90 at the same RPM as my 4.11 at 50mph. I'll see if I can get if for near-free. Don't have a clue where I can store it in my overstuffed garage. Maybe someday I'll try to get the truck back to all 1954.

Tim you had shown me the 1950 meaning of the "HE" designation a few months ago. Duh - thanks for showing me the correct date. Glad I found the ghost "2".


- Lonnie
My '54 3104
Photos that I have shared on Stovebolt via PhotoBucket are no longer available. Please contact me if you want a photo from an old post.
lonniecook [at] aol [dot] com. I sold my '54 3104 12/12/2017, but I still visit Stovebolt.

OLD STUFF ... houses, furniture, cars, wine ... I love it all

Moderated by  Dusty53, SWEET 

Link Copied to Clipboard
Home | FAQ | Gallery | Tech Tips | Events | Features | Search | Hoo-Ya Shop
Powered by UBB.threads™ PHP Forum Software 8.0.0