Inliners International Forums General Discussion Drive Train 51 truck torque tube rear end

Hello all. I am currently working on a 51 1/2 ton chevy truck that I've had for the last 12 years. The plans for the truck are a hot inline 6 engine with multiple carbs, headers, and cam bolted to a manual tranny. My question is this; if I unbolted the torque tube off of the rear axle, could I swap in a different center section (open driveline) from a later model (54 on up) car or truck? I want to keep a 50's/60's period appearance and would like to use as many of the parts I already have 'cause I'm building this thing on a budget. Also, when was the 10/12 bolt rear axle introduced? I have access to one out of a 70s chev van, but as I said, would like to maintain a period appearance. Thanks for any and all help!

First off, the car and truck rearends are similar but will not interchange, all truck gears, misc internals etc are slightly larger. A pumpkin from a late 50s truck may bolt in, however ratio choices are limited. You'll need to weld saddles on your original axle housing anyway so the whole thing doesn't flip over (the torque tube used to keep it from doing that). So, might as well go with the next generation truck rear end and have a much better ratio selection. I'm running a 1966 half ton unit under my 46 pickup which fits perfect. One more thing to consider, if you will be running an overdrive trans you could get along just fine with a lower ratio rear end, say 1957 pickup with 3.90s. Best of luck.

The later open center sections will not work with your stock carrier section.

Do you want overdrive?
Do you want 5 or 6 lug axles?
What size rims/tires were you planning on running?
What kind of driving do you plan on, mostly?

I'm considering the T5 conversion, but I have a Muncie M-22 I might drop instead. As for the 5 or 6 lug, well, I'd prefer the 6, but I'll make the switch to 5 if I have to. I'm not sure of rim size yet. Something in the 15" or 16" variety. Tire size is unknown as of yet. The truck will be a semi-daily driver with the occasional traffic light launch. I want a rear axle that I'll take whatever I decide to throw at it. Thanks for all your help.

Dear Podunkjr;

If you use a 1957 pick up rear end all will work and be strong enough etc.

Should be a 'bolt in' deal.

You will need a custom made driveshaft though.

Good luck, John M., #3370

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Not wanting to be disagreeable, but over the years I have seen several guys swap the torque tube for the center section from, I believe,a 55-59 Chevy or Gmc 1/2 ton truck. The back cover ( which un-bolts) may have to be modified. I have the pieces around my shop from verious builds and rebuilds, but never tried it. I will look into it and get back to you.---Paul

I believe you are thinking of a 3/4 ton. I have never heard of any successful changouts with the 1/2 ton center sections, but that doesn't mean something couldn't be done, I guess.

Either way, going from a 4:11 to a 3:90 seems like alot of work for an extra 5 mph. When I was in highschool, I changed out the stock 4spd/torque tube rearend in my '53 with a '57 3spd tranny and '58 driveshaft and rearend, and it wasn't really worth the time for me. Using an overdrive will help, but the first gear in most T5's will be pretty useless, if that matters to you. 3:36 gears are available for the 55-59 truck type rearend, but that is your only choice. going with something newer will give you better gear choices.

The later ('55 - '59) 1/2 ton truck center sections will bolt in - I did this on my GMC some years ago. Axles, brakes etc are no problem, but the spring perches have to be welded up because the torque tube design allows some flex for pinion torque, and without that solid tube holding everything in place, the entire rear section will rotate and soon tear up U-joints. It's easier to just replace everything from wheel to wheel. True, the 3.90 is hardly worth changing for, but gaining the open driveline allows use of an OD trans, and you have to change to an open drive trans anyway once the rear is swapped.

Ok, now that we've established that a 55 to whatever truck pumpkin will bolt into your stock axle housing. You can get new ring and pinions for this later truck 'OPEN' drive from Patrick's, not sure of the ratios. Infact check with Patrick's for all needed parts for this job like, spring perches shocks etc. Afterall it's only money!