The Stovebolt Site Forums The Shop Area Engine Shop 6-lug leaf spring rear, to replace torque tube

I have a 45 GMC 1/2 ton that is in it's final stages of restoration. I pulled the 228, and have a 302 with 4 speed. I need to find a 6-lug, leafspring rear end with the proper width. I want to use the original 6-lug rims. What should I be looking for, any recommendations??

Someone correct me if I'm wrong - but the '55 and later did away with the torque tube, and I think are the same width as the '45. 6 lug, same spacing.

Can't recall when the wider rear ends started - '66 or '72?

-Boyo

There have been a few posts that dealt with rear axle widths.One should be able to find it with a search here on the Stovebolt.
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I believe boyo is correct on the rear width on the `55

Gonna be tuff for 6 lug as ur truck has a narrow rear end. Best choices will be a 55.1 rear end or a 70's Blazer--but these are gonna be wider. I think Task force trucks (which have 6 lug) will be way too wide but haven't measured. Best resource I know: Rear Width web page

Maybe somebody else will have a better idea. Good luk

55-59 chevy 1/2t should fit but the holes in the spring pads will have to be moved forward.

I have a 80 Blazer or 1/2 ton 4x4 axle in a 51 truck, but its probably too wide for an earlier truck by maybe 2 inches.The 57 Chevy car axle in my 37 fits real nice but its 5 lug.Don't be afraid to look at axles from other makes.You may want to measure a dreaded Toyota 6 lug axle, although they look a little narrow to me.

i have a 1951 gmc 3/4 ton that im gonna put a '55-'59 rearend in, it all matches up

I have a '55 rear end in my '40 . see the link below.

If your existing brakes and axles are good, you can use the 3rd member out of a 55 or later, keep all of your existing housing & springs and keep it almost stock. Otherwise, you may want a newer rearend, such as Blazer because the 55-59 only get you to a 3.90 ratio and the replacement axles are hard to get, shoud you need one.
Because yours is a 45 , I don't think you need to do any spring perch relocation. I didn't on my 46 Chevy & it looks just fine. However, there are some subtle differences between GMC and Chevy, but I don't think this is one of them.

Richard, what do you mean by third member? Can you be more specific. I am having a hard time finding the 55-62 chevy rear ends.

Will the original hub caps fit on a 5 lug rim?? Maybe I am too hung up on the 6-lug issue to keep the rims and hub caps original. If i can find a 5-lug that has the will accept the same rim size and original hub caps, then that work work. Any comments??

aka "the chunk", "the pumpkin". It is the center part of your rear end. When you remove the axles, you can remove gears, carrier, bearings, as one piece. That piece can be bolted into the housing of your existing rearend (from which you extracted the differential of your torque tube rear end,) which means you can look through the housing because the back cover is off and you removed your torque tube r/e from the front. The third member bolts in from the front, you re attach everything inside, put on back cover, fill w/ gear lube and you are ready for a regular driveshft with u-joints.
With all that said, I opted for a complete 89 Camaro 3.42 rear end for the gearing and brake parts and it is the right fit. I had to grind the spring brackets off and weld in "normal" perches, but that was it.

As to your 5 or 6 lug issue, part of that rests on what you are going to do about brakes. It seems to be easier to get 5 lug disc kits for the front, so if you are going to change that, keep that in mind as you change the rearend.

Richard,
How about sending some pictures of this? I think I understand, but dont want to get into this with a pile of parts that dont work. I still have the original torque tube rear end, with leaf springs, brakes etc. I have never taken a pumpkin apart, but have taken on many other projects with success. Are you saying, that I would litterally remove the "pumpkin" by separating the axels and tubes from the center section, and replacing the center section with another "pumpkin" that has a good gear ratio??? If so, how can I ensure that everything will fit correctly, bolt up, etc, etc?