69 axle/71 axle (6 to 5 bolt swap)?

[brennecke]

I have a 71 chevy with a 12 bolt rear. I also have a 69 axle with a 3.73 Eaton posi in it. It is six bolt,and I'd like to stay five bolt. How can I make this work? They told me it would cost $150 to swap the posi carrier into the 71 12 bolt. Is there a way to make the 69 axle a five bolt and just a little longer? I guess it doesn't have to be longer. I could tub out the wheel wells a couple inches.

[Randy70C-10]

Not sure, but it sounds like you'd do good to pay the $150.

[brennecke]

Well, I thought that might be the case, but I was hoping that there was a cheaper solution.

[BigBlockBurris]

You can swap your axles and drums from your 71 to your 69 and then just swap whole rear-ends. It's a little labor intensive but its not anything hard or complicated and you save yourself $$$$.

BBB

[iluvmy72]

no way....pay the 150 and save yourself the Gojo.

[brennecke]

The axle shafts are longer on the 71 though.
How would I do it?

[Woody]

Well I have followed threads on this subject for a long time. See I have a 69 that has been redrilled to 5 lug. Works fine but with the 15x8 Rallys I have on it the rear tires rub the inside of the wheel wells when I turn into a raised driveway where the suspension is twisted. Not bad enough to cause wear on the sidewalls, but something I would like to fix.

Options that I have read about:
1) Swap the whole rear end (in your case this would cost you the $150 to excahge your gears/posi unit) for the 71. It is only ~3/4" wider on each side. This is what I need, wider is better.

2) I have read about someone on the board that has used the 69 housing/gears/posi unit and put 71 shafts,then made 3/4" spacers to relocate the brake backing plates (1 each side).

3) Also read about someone who has used a 69 housing/gears/posi unit and installed 71 axels, then used 73 Heavy Half rear drums (which are 2 3/4" wide) and stayed with the 2" shoes. Thus using only 2" of the drum surface.

Number 3 looks the easiest to me. That's what I want to do, but would like to have some long term data/feedback from anyone who has done it to their truck.

------------------
Woody
'69 Custom-10 Deluxe
Short Fleetside,Factory 350cid/TH400,A/C,PS,PB,Carpet
Coming soon 700R4, 350 Crate Engine, Pwr Disks...

[brennecke]

This is the information I was looking for. Anybody done it?

[STP67-72]

The 1970 model rear end is the only one that is the correct width for 71 up axles. Which is the last year for a 2wd 6 lug. You could make spacers like they said. The 69 and older should have 2 letters stamped in the axle housing, and the 70 model and newer should have 3 letters. Such as HA,HC or THA,THC on the passenger side axle tube.