Brakes on 68 Differential and 72 Differential

[Todd68Chevy]

I am sure this question has been asked before but I have not found an answer so here I go asking again. I have a 1968 6 lug that has new wheel cylinders and good brakes. I am getting ready to swap out to 72 front crossmember and 72 rear differential. I have found out something is different between the two rear ends but I am not sure what.

My questions are: Can I swap the 68 backing plates, wheel cylinders and shoes to the 72 rear end?? Can I buy 72 drums or redrill the lug holes on my 68 drums?? Thanks for your help in advance

[raycow]

The only difference I am aware of (besides the bolt pattern) is the overall width of the housing and shafts. If both rears have the same width brake shoes, I can't think of any reason why the parts shouldn't swap.

As for re-drilling the drums I have never tried it. Check the center hole size first, because the drum centers on that, not the stud holes. I think at least one of the new stud holes will overlap the old pattern, but the drum can't go anywhere as long as the wheel is bolted up tightly.

Ray

[Todd68Chevy]

Thanks raycow, that is what I was hoping but I was not sure. I thought if I could use the backing plates, shoes and wheel cylinders I might buy 72 drums and not mess with redrilling.

Todd

[SCOTI]

I had 'new' brakes on the rear of my 68 when I did the 5-lug swap. I swapped in new Moser axles & used local auto parts supplied Wagner 71-72 5-lug drums w/my existing set-up. You should be able to swap the parts over to the 71-72 axle you have (I don't think there's a need to swap the backing plates either).

[b&a72]

I am thinking of doing the same thing but the opposite, I am going from a 72 rear to a 67 rear. The 67 has 6 lug and the 72 5 lug can I just pull the axle shafts out of the 72 and put them in the 67 rear?

[b&a72]

Nevermind I guess I answered my own question. I don't want to thread hijack but does anybody know what spline axle shafts a 67 has and where to get some online?

[SCOTI]

Originally Posted by b&a72

Nevermind I guess I answered my own question. I don't want to thread hijack but does anybody know what spline axle shafts a 67 has and where to get some online?

67 housings would have 30-spline axles.

For a 71-72 12-bolt 5-lug to 6-lug swap, I would try 73-87 12-bolt 30-spline 4x4 axles.

[b&a72]

Originally Posted by SCOTI

67 housings would have 30-spline axles.

For a 71-72 12-bolt 5-lug to 6-lug swap, I would try 73-87 12-bolt 30-spline 4x4 axles.

I am doing the 6 lug to 5 lug swap would this still work? And are the axles the same length as the 67 axles?

[SCOTI]

Originally Posted by b&a72

I am doing the 6 lug to 5 lug swap would this still work? And are the axles the same length as the 67 axles?

No, it is not the same. 71-72 housings/axles are the same width as 73-87's. Pre-71 housings/axles are .750" shorter each side. If you have an OE 6-lug housing, you'll need to buy replacement axles (CPP, ECE, Moser, etc...); weld, machine, & re-drill your existing axles; or swap a later 5-lug housing into place (71-72 direct swap for coil suspension; everything else requires possible spring mount mods).

[Todd68Chevy]

Once again a lot of good information. Thanks everybody