Click on image for the lowdown. 
====
| | | Forums66 Topics128,196 Posts1,057,388 Members48,469 | | Most Online14,466 Apr 26th, 2026 | | AD Chevy Trucks 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!
| | 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! | | | | Joined: Feb 2008 Posts: 158 Shop Shark | | Shop Shark Joined: Feb 2008 Posts: 158 | Where can I get a 3.90 ring and pinion set for the rear axle on my truck. And where can I find a transmission rebuild kit for the factory 4 speed in my 1946 3/4 ton | | | | | Joined: Jun 2008 Posts: 106 Shop Shark | | Shop Shark Joined: Jun 2008 Posts: 106 | I think the '54 1/2 ton trucks had a 3.90 rear end. ANyone know where we can verify that? | | | | | Joined: Feb 2008 Posts: 158 Shop Shark | | Shop Shark Joined: Feb 2008 Posts: 158 | The 1946 3/4 ton rear end is an open drive system or a propeller shaft. And the 1954 chevrolet 1/2 ton rear end has a axle tube or a enclosed drive shaft. I found a ring and pinion set for a 1946 3/4 truck but it had been discontinued on www.Americanclassic.com. | | | | | Joined: Dec 2004 Posts: 1,897 Shop Shark | | Shop Shark Joined: Dec 2004 Posts: 1,897 | 46-72 eaton rear ends have a lot of interchangeable parts. I believe you will find a 4.11 pumpkin that will interchange in 67-72 3/4 tons that have coil spring rear ends. I have never done this swap, and skimmed some other 3/4 ton rear end threads to come up with that answer. 3.90s seem to be very rare. The late Art Hauser had offered them. I'm not sure where you are going with your truck, but 4.11 gears and an overdrive would work pretty well to move your truck down the road. Taller tires could make up the difference between 3.90 and 4.11 | | | | | Joined: Mar 2006 Posts: 143 Wrench Fetcher | | Wrench Fetcher Joined: Mar 2006 Posts: 143 | The 55 first series have an open drive line and a 3.90 rear-
| | | | | Joined: Feb 2008 Posts: 158 Shop Shark | | Shop Shark Joined: Feb 2008 Posts: 158 | Is that in the 1955 3/4 ton truck or is that in the 1/2 ton model? | | | | | Joined: Mar 2006 Posts: 143 Wrench Fetcher | | Wrench Fetcher Joined: Mar 2006 Posts: 143 | I believe all the 3/4 ton AD trucks had open drive lines-- 55 first series was the first open one for 1/2 tons. Check for the Chevy manuals online (Tech tips area?). Come on, guys, help me out here. I think the person doing the manuals is Kevin Hardy????? | | | | | Joined: Mar 2006 Posts: 143 Wrench Fetcher | | Wrench Fetcher Joined: Mar 2006 Posts: 143 | I believe all the 3/4 ton AD trucks had open drive lines-- 55 first series was the first open one for 1/2 tons. Check for the Chevy manuals online (Tech tips area?). Come on, guys, help me out here. I think the person doing the manuals is Kevin Hardy????? WHOOOPS___ it is Keith, not Kevin. PS- Keith, please forgive me - it's the fuzzy old brain__ sorry! | | | | | Joined: Nov 2005 Posts: 1,048 'Bolter | | 'Bolter Joined: Nov 2005 Posts: 1,048 | Does your 3/4 ton have 6 bolt or 8 bolt wheels | | | | | Joined: Dec 2004 Posts: 1,897 Shop Shark | | Shop Shark Joined: Dec 2004 Posts: 1,897 | Good question Kip
46 was the 1st year for the 8 lug 3/4 ton. It is quite possible that he has a earlier pickup that has been titled as a 46. If He has an 8 lug rear end, the info I gave above would be correct. If he has a 6 lug rear, I would think the information about the 67-72 3/4 ton rear ends would be useless. | | | | | Joined: Nov 2005 Posts: 1,048 'Bolter | | 'Bolter Joined: Nov 2005 Posts: 1,048 | | | | | | Joined: Feb 2008 Posts: 158 Shop Shark | | Shop Shark Joined: Feb 2008 Posts: 158 | Its a 1946 chevrolet 3/4 ton all original with the stock 8 lug I bought it for $700 dollars last week from a guy on the Jalopy Journal. I also have a 1946 chevrolet 1/2 to I'm going to use the cab off it on my 3/4 ton. But thanks on the information on the rear axle it just gave me alot of options for parts. And do yall know if a GMC 302 straight 6 will fit under the hood of a 1946 Chevy and does it have the same block size as a 235 and the same bolt pattern for a Chevy bellhouseing?
Last edited by Oldtruck1946; 08/16/2008 5:45 AM.
| | | | | Joined: Feb 2008 Posts: 158 Shop Shark | | Shop Shark Joined: Feb 2008 Posts: 158 | So where can I find a 3.90 or a 3.73 ring and pinion set for my 1946 Chevrolet 3/4 ton truck? | | | | | Joined: Jun 2008 Posts: 47 Wrench Fetcher | | Wrench Fetcher Joined: Jun 2008 Posts: 47 | Hi. Your rearend should be an Eaton HO52 or Eaton HO72. The carrier with the ring and pinion setup interchange directly with a 1967-72 Chevy or GMC 3/4-Ton truck. The highest stock gear ratio is 4.10. I made the swap on my '49 Chevy 3/4-Ton and it worked out great. You should be able to find a rearend carrier with 4.10's by surfing 67-72chevytrucks.com.
Good Luck! Dan M. | | | | | Joined: Feb 2008 Posts: 158 Shop Shark | | Shop Shark Joined: Feb 2008 Posts: 158 | So where can I find a new set of gears for my rearend. I also found a 1964 eaton rearend that does not have the backlash screw on the side of it. will it be any easier to find gears for them? | | | | | Joined: Oct 2003 Posts: 5,152 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Oct 2003 Posts: 5,152 | So you're asking the same questions in two different threads...
The rear under your '46 and the rear from a '64 are the same rear. The pumpkins will swap and you have the same very limited options for ratios.
The GMC 302 will bolt to the Chevy bellhousing. You'll need the GMC flywheel. You will need to drill new holes for the front mounts. Check the Tech Tips section for more information on swappnig the 302.
1955 1st GMC Suburban | 1954 GMC 250 trailer puller project | 1954 GMC 250 Hydra-Matic | 1954 Chevy 3100 . 1947 Chevy COE | and more... It's true. I really don't do anything but browse the Internet looking for trouble... | | |
| |