The Stovebolt Site Forums The Shop Area Engine Shop 1/2 ton torque tube swap to a 3/4 ton diff

Other options for the '53 GMC 1/2T...
I ran across this as a site, but can't find it again. Somebody swapped the diff and put a 3/4T diff in it, so you could run a driveshaft and u-joints. Has anyone heard of this option, other than swapping the torque tube for a '72 Blazer axle?

I ran a 55 car rear in a 53 GMC.I had to change the transmission too.I made a bracket to recenter the rear,but I think you can turn the springs around to recenter.(The torque tube alinement pin is not in the center of the axle).

My concern would be the even lower gearing in a 3600 rear. My question is why are you interested in chqnging it if it isn't to gain a higher ratio?

I might like a higher ratio too but the truck doesn't get driven enough to ever be cost effective. Besides mine will run 65+ MPH now although it is screaming so 50 is fine and that matches my brakes as well.

Well for one, my "Tinker's Toy" won't be put back together from stock parts. Two, there is so much missing to the '53, that I have the option of re-assembling it as I see fit. The swap of the innards of the torque tube to something more modern [hook-up to a THM350], just shows me that it'd be easier to hunt down a '72 2WD Blazer axle and springs, and make my own perches. If the ratio is too high, I can get something lower at a buddy's rear end shop.

Another question for the rodders: is it possible to "mate" modern [S-10] steering linkages and tie rod ends to the '53 spindle arms on the straight axle? My truck has no steering box, and I'm thinking of using more modern parts that will be easier to get locally, rather than a special order online or in a catalog.

There's a few issues with what you're asking about. With the torque tbe drive, there's no "swapping innards" to make it fit modern parts, they're pretty much stock only. Since you're wanting to run a TH350, you can eliminate the torque tube altogether. An easy fix for the rearend, besides swapping it out, would be to use a '55-'62 3rd member and weld up the pivots on the spring mounts. Those come in 3.90 (common) 4.10, and 3.38 gears. The 3.38 is also available in an aftermarket gearset.
On the steering, the S-10 parts won't work. They're 2 completely different styles of steering linkage, with the '53 having a 1 peice solid tire rod, the S-10 having a paralellogram style. Best bet would be to use a tie rod conversion kit and new tie rod from one of the parts suppliers, and perhaps a power steering conversion kit as well, since you do not have the box. I've been seeing that the Toyota box works very well, and can be fit into the stock location. You might do a search on thet for more information.

Thanks, Mr. Bill.
Yes, the research is not complete yet, so I will keep asking the questions until I get enuff of the right info to move forward on the project. I figure keeping the 6-lug pattern makes sense as the truck came with wagon wheels. I have previously owned a '72 K-5 Blazer, and this will be the rear axle of choice to acquire.
The new linkage idea with the existing front axle setup may be best as will the roller bearing conversion set. I have LMC catalogs handy. Have posted a want ad for the stock steering box, column and wheel, to swap the box and rear fenders for them. I will be building a short-sided dump box for this.
Also, I prefer to assemble this GMC Truck with just GM parts.
And I suppose I will eventually post an ad for the torque tube axle, minus the drums.