51 Chevy 3600 Differential/Center Section Options
 

I have a 1951 Chevrolet 3600 with an Eaton HO52 rearend (8 lug axles, 4.56 gears). It has an open driveshaft (no torque tube). I would like to keep as much original equipment as possible so I’m looking for options for a direct differential/center section swap that can get me 4.11 gears or lower to help with cruising speed.

I have heard that the 67-72 C/K 20 models should be a direct swap, anyone know of other options to get me a little better gear ratio?

Re: 51 Chevy 3600 Differential/Center Section Options
 

Here is the exact info you are looking for, Finding a 68/72 coil spring C20 with 350 and automatic in a wrecking yard with a good third member might be a bit of a challenge. In truth the hard part will be finding a good donor.

https://www.stovebolt.com/techtips/a...Ton%20Upgrade/

This is good info that I am saving to my favorites as I see people ask the same question all the time. I'd be looking more at 69/72 potential donors though. GMC is leaf spring and often as not has a Dana 60 as my 71 GMC does.