| |
Click on image for the lowdown. 
====
| | |
2 members (J Lucas, pauld),
123
guests, and
2
robots. | | Key: Admin,
Global Mod,
Mod | | | Forums66 Topics128,183 Posts1,057,263 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: Dec 2011 Posts: 40 Wrench Fetcher | | Wrench Fetcher Joined: Dec 2011 Posts: 40 | I am in the process of swapping out my 4.57 gear set for a 4.10 one in my HO72 Eaton 1 ton axle, in my 46 3/4 ton Chevy pickup...as part of the swap, I would like to convert to a one piece or two piece open drive shaft...
My question is...what problems will I encounter in doing this, or do I have to keep the torque Tube while using my old "original" Granny 4 speed? I really don’t want to keep the torque tube if possible.
| | | | | Joined: Jan 2001 Posts: 5,337 'Bolter | | 'Bolter Joined: Jan 2001 Posts: 5,337 | It is not as easy to convert the early nonsynchro transmissions as the SM420.
It would require a main shaft, yoke, and extension housing from a 1 1/2 or 2 ton.
Might be easiest to keep the inclosed front shaft.
See the USA in your vintage Chevrolet! My Blog | | | | | Joined: Dec 2004 Posts: 1,897 Shop Shark | | Shop Shark Joined: Dec 2004 Posts: 1,897 | 1941-1954 3/4 ton trucks used a hybrid driveline... torquetube to carrier bearing then convetional driveshaft to the rear. No need to change that with a gear swap. However if swapping transmissions, the one piece driveshaft may be easier to fabricate.
Of course a transmission swap has it's own challenges on a 46. The transmission to bellhousing bolting pattern is different than the later chevy and gmc trucks. Most transmission swaps will involve using a modified 1948-1954 bellhousing. An adapter plate could also be used between the old bellhousing and a newer transmission.
I have plans of swapping out the non-syncro crash box in my 1940 gmc project to a fully syncroed nv4500 5 speed. | | |
|
|
| |
