Technical Early Chevy Truck Open Drive Conversion - Solved

Hello Fellow H.A.M.Ber's!

I have a 49 Chevy 1/2 ton pickup truck that has a 1953, 235 inline 6 cylinder motor with a 3 speed closed drive transmission. I have been working for some time trying to figure out a way to make this truck open drive, as I wanted to use a more modern rear end. Today I figured it out and wanted to let you all know how I did it!

First off I pulled the engine out of my truck so that I could work on it easier.


Next I found and acquired what I believe to be a 1961 Pontiac Laurentian Open drive 3 speed gearbox.

I did some measuring and found out that it has the exact same bolt pattern as my original closed drive 53 truck ******!

So I removed my closed drive ******,


And tried on the 61 Laurentian gear box....

and it fit perfectly! I didn't have to touch the clutch disc, pressure plate, pilot pushing or throwout bearing! The input shaft length, size and spline were identical!

The only difference I found is that I will need to get a longer set of bolts with nuts for the bottom 2 mounting holes. On the original 53' truck gear box, these were threaded and you tightened them from the inside of the bell housing. On the 61' Pontiac, it was the bell housing that was threaded, so I ended up with a smooth hole all the way through, thus requiring a longer set of bolts with nuts.

The last thing I had to do was change the shifter levers. I did this by taking the shifter cover and levers of the 53' truck ******....


and put them on my 61 Pontiac ******.

This fit near perfectly, and now it shifts and best of all, will work with the column shifter in my truck!

So there you have it, open drive conversion for a 49' chevy pickup with a 53' 235 motor!



Let me know what you all think - and if you have any questions, please don't hesitate to ask!

Cheers! David

 

the 61 pont. trans looks like the same one used in 58 to 64 3 speed chevs?

 

Possibly, though I'm not sure. It seems to me that that year of Pontiac used the same motor too - a 235, so I think the answer is yes.

 

Job well done.

 

Thank you!

 

Nice, so what's the story on the rear axle? I understand that the 3rd member from a taskforce truck will fit the rear axle housing of a A.D. truck.

 

I was wondering the same on the rear axle.

 

A Task Force rear axle fits in real well. You do have to get a set new spring pads to put the axle on top of the springs with or go old school and cut the pads off the axle and move them to the bottom. Then you have to drill holes for the spring bolts to go in 1-3/4 inches in front of the center line of the axle to center the axle in the wheelwell.
Ebay item: 1-3/4 inch wide spring pads that fit your stock rear springs (could be used as a plan to build your own.
331423425537

 

55 - 62 Canadian Pontiacs used a 261 cu in Chev truck six cylinder that interchanged with the Chev 235. It is not surprising they used the same trans and drive train, there was a lot of Chev in Canadian Pontiacs.

 

I decided to go 5 stud on this truck, so I am using a 80's chevy 1/2 ton rear axle.


I cut the axle pads off of another axle, and put them on this one....

I also put a piece of 2x4 steel tube in between as a lowering block - with the axle on top. This gives me the ride I want. I like this axle a lot better than the original axle because I can now use weld on back disc brakes; and I wanted the back bolt pattern to match the front - which is going to be a 5 stud, bolt on disc brake kit.

 

I decided to drop in a more modern 80's chevy 1/2 ton rear end. Check my other post for pictures.

 

I decided to use a 80's chevy 1/2 ton rear end - a 12 bolt I think they call them. Check out my other post for pictures!

 

Very good point! I have two complete canadian pontiacs and you're right about them having lots of chevy in them.