The Stovebolt Site Forums The Shop Area Engine Shop 1954 3600 rearend

I would like to know if I could put a set of higher gears in the original housing or would I be better off changeing the whole rearend to a modern 3/4 ton, and which ones will fit? I do not know the original gear ratio but I know it's too stout. When I am all done either way I want to use stock hub caps and wheels for the 54. Is this going to be a problem?

Standard gears in your rear are 4.57. The only option was 5.14. Later on 4.11 gears were available for that rear. Those three are your only real options unless you change rears.

Are you also changing the motor? I know at least one guy who swapped rears and ended up with a truck that would no longer move a load. He put 3.42 gears under a 1-ton and was never happy with the result.

Think hard about how you intend to use the truck before deciding which route to take.

Welcome aboard wiley. Well, there's 2 ways around this; 1, find a 3rd member from a '68-'72 3/4 ton Chevy with the 350/automatic combo. Those tend to have a 4.10 ratio. There is also a VERY RARE '72 variant that is a 3.55 gear, but those are virtually impossible to fins (I've only ever seen one). Option #2, swap the entire rearend to a late 70s-early 90s Dodge or Ford 3/4 ton van Dana 60, the width is just about right and they are 8 lug. 3.55 is the common ratio on those, but most are also semi-float, so you may give up strength if use that version. I have also heard that the 14 bolt from a '70s-'95 Chevy Van is the right width, too. You'll have to seek out tha 1 ton van for that, not sure of the common ratio on those.

I intend to use the original 235, and the truck will be driven around town occasionally.I have 2 other 3100 trucks I can pull the front and rear axles out of, but then the 3600 won't be original. I don't know if this will de-value the truck or not.

Hi Wiley -

Longbox55 Bill is correct. Your factory original 3/4-ton rearend should be an Eaton HO52 or HO72 which was also used in'67-'72 3/4-ton Chevy/GMC trucks. This is a direct interchange with your stock rearend. You should be able to find a 4.10 third member reasonably priced on www.67-72chevytrucks.com. Most of those guys are the 4-wheeler types that are looking for lower rearend gears to replace their 4.10's.

I was lucky enough to find a 4.10 Eaton HO72 with "No-Slip" posi-traction for my 1949 Chevy 3600. Inland Truck Parts & Service did a mild rebuild on it for me. It was an easy swap with no problems. Parts are still available for the Eaton rearend, but they are a tad pricey.

In general, I like the clean round look of the Eaton HO52/72 rearend and like the idea of keeping my truck as original as possible, yet more drivable at today's highway speeds.

If you have any questions, please let me know.

Thanks!
Dan M.

Yes Dan, my question is, could you give me the numbers that are stamped on the center section that your put in your truck? I put a 4.10 in my '50, 3600 last summer and am very happy with it but I would like to keep my eyes open for a posi.

Thanks
Denny Graham
Sandwich, IL

Denny, Did you ever come up with a speedometer cure ?