Click on image for the lowdown. 
====
| | | Forums66 Topics128,203 Posts1,057,286 Members48,467 | | 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: Apr 2005 Posts: 381 Shop Shark | | Shop Shark Joined: Apr 2005 Posts: 381 | Was an Eaton rear axle standard equipment in a 1948 Chevy 4400 series dump truck? The axle shafts have 10 splines and 21 teeth on the outer end. | | | | | Joined: Feb 2006 Posts: 1,867 Shop Shark | | Shop Shark Joined: Feb 2006 Posts: 1,867 | I replied with this on the oldgmctrucks.com site.
No. I don't believe the name for the single speed rear really had any designation other than being called a GM single speed rearend.
I also don't believe all the 2 speeds are even Eatons, although they can share some parts.
Jeff
| | | | | Joined: Apr 2005 Posts: 381 Shop Shark | | Shop Shark Joined: Apr 2005 Posts: 381 | Hi rustednuts, Thanks for the reply. wbrowne | | | | | Joined: Mar 2004 Posts: 6,236 'Bolter | | 'Bolter Joined: Mar 2004 Posts: 6,236 | I'm not aware of any Eaton Rear Axles being factory installed by Chevrolet prior to 1956 when they introduced the 9000 and 10000 Series (2-1/2 ton) trucks. I'm also not aware of any shared parts between Corporate GM and Eaton Rears...maybe a bearing or seal? Both GM and Eaton made Single and 2-Speed rears... Mike B  | | | | | Joined: Dec 2002 Posts: 2,549 'Bolter | | 'Bolter Joined: Dec 2002 Posts: 2,549 | Before 1956, the 2 speed rear axles in Chevrolet's were Timken rear axles. Eaton 2 spd. rears, were available in GMC's much earlier. | | | | | Joined: Mar 2004 Posts: 6,236 'Bolter | | 'Bolter Joined: Mar 2004 Posts: 6,236 | Thanks Spanky, I didn't know that! I knew GMC started using Eaton's way before Chevrolet did... Mike B  | | | | | Joined: Dec 2002 Posts: 2,549 'Bolter | | 'Bolter Joined: Dec 2002 Posts: 2,549 | Yeah Mike, I recently removed a Timken 2 spd. from a '55 1st series Chevy COE that I parted out. Had it, along with the axles sitting in my moms back yard. Would you believe someone came along, & stole it out of her fenced back yard. | | | | | Joined: Mar 2004 Posts: 6,236 'Bolter | | 'Bolter Joined: Mar 2004 Posts: 6,236 | That takes a lot of nerve. Ya think they knew what it was or was it taken cause scrap is so high? Mike B  | | | | | Joined: Dec 2002 Posts: 2,549 'Bolter | | 'Bolter Joined: Dec 2002 Posts: 2,549 | I don't know Mike. They took the differential, but left the axle shafts, & two junk SM420 transmissions, that were next to it. | | |
| |