Rear Axles 1/2 ton 3/4 ton questions?

[bsgmcc20]

Ok Since most would like a simple answer. how about a couple of simple questions guys. If you can help that would be great. Now this is for most the non-4x4 types, since that is a different rabbit. I did some searching of the site and came up with a few hits.

http://67-72chevytrucks.com/vboard/s...d.php?t=344643
http://67-72chevytrucks.com/vboard/s...d.php?t=323812
http://67-72chevytrucks.com/vboard/s...d.php?t=323386 4x4



1. If you have a stock axle what is the trk and axle type? and do you know the width?

2. If you have a Swapped axle, what was your donor vehicle and what is the ride that will have the axle in?

3. This is going to be tough since i am shooting for 67-72 c10 and c20 for now.


If i can get enough info it would help to make a quick reference guide, to help anyone who is surfing for the info on axles.

[clay68c10]

If you're up for a little fab work, the mid 70's Lincoln 9 inch is the right width and 5x5 bolt pattern. Most of them also came with disc brakes. I suspect that era LTD and Torino would also work.
The only drawback I found was that those disc brake components are kind of spendy, but they are off the shelf items and they have the parking brake built in.

[bsgmcc20]

Boy I guess its time for me to hit the books and the Rear axles with a tape measure. argggg

[Longhorn Man]

honestly, I don't even understand the question.
Are you looking to upgrade the rear on a C/10?
Are you looking to upgrade the rear on a C/20?
Are you converting a C/20 to a C/10?

[bsgmcc20]

Sorry if it was a confusing post. been busy with my truck.

My Thoughts were to locate Donor Rear axles that would work for a 67-72 c10 or c20 non-4x4. I am assuming the axle width doesnt differ between the years.

was looking for examples:

1981 Chevy c20 non 4x4 with a 454 turbo 400 and Corporate 14 bolt rear axle. So this Corportate 14 bolt will have the spring perches and shock mounts changed. if i were to want to use it as a donor.

Since i have noticed that 3.54 is a common rear for the c20 . I think If memory serves you(Longhorn man) had posted the info about the 3.54 gear ratio. So I was looking for Donor trucks by Chevy or GMC to use as a replacement for a 3.54.

[Longhorn Man]

in te 67 - 72, the 3.54 is only as common as a big block. With only a couple documented exceptions, that ratio only came in big block trucks.
So you just want better gearing... don't care if it is a 5, 6 or 8 lug hub.... right?

[Tx Firefighter]

My head hurts.

Are we looking for a 5,6, or 8 lug rearend? Coil or leaf spring ?

[bsgmcc20]

Originally Posted by Tx Firefighter

My head hurts.

Are we looking for a 5,6, or 8 lug rearend? Coil or leaf spring ?

Ok c20 8 lug Leaf sorry for not being more clear. there tx Firefighter

[bsgmcc20]

Originally Posted by Longhorn Man

in te 67 - 72, the 3.54 is only as common as a big block. With only a couple documented exceptions, that ratio only came in big block trucks.
So you just want better gearing... don't care if it is a 5, 6 or 8 lug hub.... right?

lets start with Big Blocks since i have one and a 3.54 gear rear end.

What axles do c20 have ? eaton ? dana? Corporate?

Can I use a 3/4 ton rear out of a different year c20? I realize that there is differences in width and Spring perch location. But for the most part I assume you can mcgyver any axle to what you might need. Bar the fact i dont want to shorten axle shafts ect. I am thinking crossover. with out cutting the width down.

[haysonj]

Originally Posted by bsgmcc20

lets start with Big Blocks since i have one and a 3.54 gear rear end.

What axles do c20 have ? eaton ? dana? Corporate?

Can I use a 3/4 ton rear out of a different year c20? I realize that there is differences in width and Spring perch location. But for the most part I assume you can mcgyver any axle to what you might need. Bar the fact i dont want to shorten axle shafts ect. I am thinking crossover. with out cutting the width down.

I got a 14 bolt Corp from a 73 and moved the perches to make it fit. Lots of gear choices, I put 4.09 to match my front dana 44

[Longhorn Man]

Originally Posted by bsgmcc20

lets start with Big Blocks since i have one and a 3.54 gear rear end.

What axles do c20 have ? eaton ? dana? Corporate?

Can I use a 3/4 ton rear out of a different year c20? I realize that there is differences in width and Spring perch location. But for the most part I assume you can mcgyver any axle to what you might need. Bar the fact i dont want to shorten axle shafts ect. I am thinking crossover. with out cutting the width down.

If you have a 3/4 ton big block, then you should have the Dana. The base rear end in non big block 3/4 ton, and in all one tons, was the Corperate rear, with an eaton diff in it. Most people around here just call it the eaton rear.

If you can cut and weld the spring pertches, and shock mounts, then you can install any C/20 rear out of anything ever built pretty much.
If you can't cut and weld properly, and can't pay someone/pull a buddy favor, then you are stuck measuring what you have, and what you come across.
You say you are thinking crossover.... what are you crossing?

[bsgmcc20]

Originally Posted by Longhorn Man

You say you are thinking crossover.... what are you crossing?

What I was thinking is what haysonj said using a 73 corporate rear in what i assume was not a 73.

So Here is my inexperience comes in. The 3.54 i havent taken the cover off in my "Factory Stock 70 gmc" . My thoughts are as i had the truck up on jack stands. when i spun one tire the other one spun reverse direction. I was told by a buddy who is a 4x4 Toyota nut. That the 3.54 is a posi and its in need of service to "ungunk" the clutches. So i was given a 81 chevy corportate 14 bolt as a replacement.

I wanted to get the trusted advise of you guys on the site here. Since Some of you eat sleep and breathe truck. No offense intended.

So i was thinking of "relocating" the perches of the 14 bolt and putting it in place of the dana that is in the truck now.

I wanted a Posi rear for this truck due to the Area's that i drive here. 1 1/2 mile dirt/mud road on a regular basis.

And the present One tire traction i am getting is disappointing on the up hill sections.
Do I clean and fix if possible the 3.54 or do i swap it for the 14 bolt?