The Stovebolt Site Forums The Shop Area Driveline Replacement rear end

Question to all, what replacement 6 lug axle are you using in the 3100. I have a 1950 and want to change to a more modern rear with 6 lug.
Thanks
Tom

Hi Tom,
You're likely to get about 100 suggestions. I'm using a 1969 Chevy pickup rear end (C10) that was originally mated to a 396 and automatic. Width is correct. You will have to cut off the OEM mounts and weld new spring perch mounts on, but otherwise the 12 bolt rear end was a very good one. Hope this helps.

Thank You Sir

What transmission do you plan on using? I have a '50 3100 which came with a Saginaw three speed and a 3.08 six lug rear axle, and 28" high tires (stock).
The truck could not get out of its own way in first gear. It did go down the highway at 65 MPH without the engine screaming. However, each upshift began with excessive lugging, required revving it up excessively prior to the next upshift in an attempt to reduce the lugging upon the next upshift.
I couldn't live like that so I swapped in a T-5 from an early 80s S-10. It has .72 overdrive. You can run some pretty steep rear end gears with that 5th gear ratio. I used a 2001 Nissan Xterra 6 lug axle with 4.64 ratio and limited slip. It was a dream to install in the truck. Right width, 1950 rims bolt on, easy to adapt parking brake. This rear axle is basically a Dana rear axle. I went with 30.5" tires to dial the setup in. The 28" tires made 1st gear a granny gear which was not of much use. The 30" tires make first gear act like first gear now.
I can pull stumps and drag them down the road at 70 MPH.

Ok all thanks for the in put. I got the 1969 rear end and it will work, but I am having to find spring anchor plate that will work with the 3/4 wide springs. The existing set up is too narrow. Not sure what plates to get. Thanks to all who comment.

What is the gear ratio of that '69 rear end. I know that it will fit and accept stock 6 lug rims, but if it is 3.08, you won't get the best that the T-5 has to offer.

It is actually a 3.07. I've explained the T5 ratios here many times before, but here we go again.

The OEM overall starting line ratio in the 1952 pickup was 12.08 (2.94 x 4.11). If you choose a T5 with the ratio chain which starts with 4.03 (first gear) and ends in 5th with .86, everything will be Jake. First gear starting line ratio in that case will be 3.07 x 4.03 or 12.37...a mere shade more oomph per rpm than you'd get with 12.08 but not enough to discuss. Then when you get to 4th gear, the 3.07 v the 4.11 will give you a 25% advantage by dropping to 3.07 (1:1). And then when you shift into 5th, you will have 3.07 x .86 or 2.64. If you had a 3 speed with overdrive and a 4.11 rear (which was what GM commonly set up), your overall ratio in 3rd and overdrive would be .7 x 4.11 or 2.87. But I use 15 inch wheels and my tire diameter is smaller as a result, so divide my 2.64 by .94 and you get 2.81 which is virtually the same as 2.87. So as I've said before, I think I have about all the advantage one could get.