The Stovebolt Site Forums The Shop Area Driveline Rear axle options for open driveline

I'm going open driveline on my '46 1/2 ton. 235 engine, stock bellhousing adapted to a T5 or similar (depends on what I can find cheap). I need to change to an open rear, and I would also like bendix brakes. I've got a '56 front axle/brakes for the truck which should match up well to a '55-'62 rear axle but this is being a bit hard to find. I have a couple questions about later axles, '63-'72. I want to stick with 6-lug for one thing, and I'm shooting for a rear axle ratio of between 3.73-4.11. Besides '55-'62 are there axles that are particularly good or bad from a width and mounting standpoint? Also, are the rear wheel cylinders the same bore as my '56 front axle or will I need a proportioning valve for a later axle, like a '67-'72, which seems to be much easier to find?

Why not use the best brakes available and upgrade to disc in the front. I assume the t5 swap will let you drive faster.

As for the proportioning valve question... put it all together and make some controlled panic stops on both dry and wet pavement. If the rears lock up to quickly you will need a proportioning valve. It should not be too difficult to cut one in and bleed the system.

John, If you are not putting out a whole bunch of horsepower, the rear axle from a 4wd S10 blazer is exactly the same width as the stock rear. I am using one on my '39 GMC 1/2 Ton. It has 3.43 gears and disc brakes. I had to send the stock axles off to have them welded up and redrilled for the stock 6-lug pattern.

I'm not putting out a whole lot of hp. It'll be a stock-ish 235.

Thanks for the suggestions, but I'm not trying to change that much about the truck and I think disc brakes would bother me. Especially up front, but the truck is getting a flatbed and I think rear discs would be obvious. 4-wheel drums is fine with me. I plan on keeping the under-floor m/c as well. Just looking to make it that much safer with a set of bendix rear brakes, since I need an open axle anyway.

I don't suppose there were any drum-brake rear blazers/s10's?

Hello, What is the spacing for the axle you got as 54.5 or 55". Did you keep the leaf springs or go coils? Do you have any pics? thx

I have a 46 1/2 ton and it has a 235 with enclosed driveshaft and needing some insght for a decent rearend swap, thanks bill

At this rate I'll win an award for slowest restoration of a truck. I ended with my ideal setup. A very good HAMB member up in PA went to a couple good local yards he deals with and found a trans and rear for me. I've got a T5 from an '89 S10. Forward shifter location and cable tailshaft housing. It's grungy and needs seals/gaskets but it feels smooth and is supposed to be from a running/moving vehicle.

Same guy scrounged me up a '59 1/2-ton rear with 3.90's. Complete from drum-to-drum and even including springs and shackles. Definitely needs the brakes rebuilt, but otherwise looks good.

So, it's going to be a '53 235, a T5 trans, and a 3.90 rear for my '46 pickup. All 6-lug, manual drums. Plan to adapt the T5 to the stock bellhousing and keep all my existing mounts. More to follow (who knows when though).