The Stovebolt Site Forums The Shop Area Driveline 1951 Chevy driveline upgrade

Gents,

I figured that i would document what i have been doing in case it helps someone out in the future. I don’t currently have any questions that need answering.

In our 1951 Chevy 3100 with a (‘61) 261, we are currently putting in a ‘61 Berg Warner 3 speed with OD as i wanted to keep the column shift aka anti-theft device. Here are somethings that i have learned along the way.

1. The transmission cross member comes out easily after removing 10 bolts and it makes the installation of the transmission easier with the longer transmission. (I’ve never had to take it out previously)
2. If you are running an upgraded brake system that has a portioning valve, you might have to rerun some brake lines as the solenoid may hit a line.
3. There is always something you didn’t consider….. my rear passenger brake was leaking on my brake pads, so i will not only be fixing lines, but i will also be replacing brake shoes and cleaning.

Next week, i will be cutting off the perches and setting the axle into place so i can set the pinion angle (TREMEC app can help with this) for drive shaft measurement.

Depending on the driveshaft welder, i should be back on the road within 2 weeks. Stay tuned for more! Thanks to my brothers on here who have helped me get ready for this.

Chris

Wrong Forum Chris, move it to the Driveliine... Come on Moderator do that thing...

Got it where it needs to be Craig.

Chris - How about some pictures to document your transmission swap and switch to open driveline? Would surely help folks see what you're describing.

That was meant as a jab at Chris...not you Dan.. I have been waiting on Chris to do this conversion for awhile now..

Tut,

I was just checking to see if you were moderating properly… thanks for catching my error.

GDAD,

I will be taking more pictures this week to add.

Chris

Edit: any requests on certain photos? If not, i will just start taking them and uploading

How did the column shift work out? I put a Saginaw 3 spd. od. in a ‘53 2 door and tried to use the column shift. It worked, but not very good. I experimented with the shift arms, but never could get it to shift smooth. I finally took the od. unit off the 3spd and put it on a 4spd. and a floor shifter. I ask because my boy has a ‘51 GMC and we bought a Saginaw all synchro 3spd. w/od. to put in it. He also wants to keep the column shifter.

jay d
The GM Muncie OD has similar shift components that can be used in the early trucks
Since neither of the vehicles you cited came with anything close to a Saganaw 3 speed overdrive
you will need to modify and/or fabricate the shift levers and arms.
Check with member Robert Cranston. He has a 49 GMC with a Saganaw w/OD trans in it.
Fred

I put a Saginaw straight 3-speed from a 1968 van into my 1950 GMC around 1980 and drove for near 40 years until I changed it for the same transmission with the BW overdrive around 2024. I do not have shift linkage interference problems. The rods from the column are original 1950. I don't remember if the 2nd/3rd bracket is from that van or is original 1950. For the 1st/R bracket I made what I thought would work out of cardboard just to look at in the two positions. I then made it out of a piece of 1/4" plywood then drove the truck to check. When I had it working I made the one shown in the photo. It shifts well and does not interfere with the OD solenoid. An additional bonus about this transmission is that I was able to easily bolt the tail shaft to the original cross member. The OD version tail shaft bolts the same way.

I'm not home now, but if this information is useful, then I can get better photos when I get home.

Sorry Robert, I messed up your name. Fred