rear brake drums
 

I have a 81 GMC 2wd 1/2 ton donor truck to upgrade my 69 to PS/PB and it looks like the rear brake backing plate will bolt on to the 69 rear. What I want to know is would 81 4x4 drums match up with the backing plate?

Also, if I swap the 69 rear for the 81 (lot of work) would 4x4 axles fit the 2wd rearend?

The drums and discs are shot, I bought 6 lug discs from GMC Pauls for the front conversion and would like to upgrade the rear also. Trying to get some ideas/options before I head off in a direction I'll regret latter $$.

Thanks

Re: rear brake drums
 

Zeke I'm going to copy this to the 67-72 forum. I think you will get a better response there...:)

Re: rear brake drums
 

I doubt if you will gain any rear braking power by switching to the 81 unless they are the HD type. You will have to deal with the emergency brake cables also. Do you have other reasons to switch to the 81 3rd member?

If you were closer I would give you a nice oem 67-72 rear brake setup as I went to disc on the rear,

Re: rear brake drums
 

I Bolted The Backing Plates & Complete Drum & Brake Assy. Off Of A 75 ONTO A 71 12 BOLT. They Were 2 5/8" Instead Of The 2" Wide Shoes That Came On Our Trucks. It Made A Very Noticable Difference. ;) John

Re: rear brake drums
 

ARe those 2 5/8" shoes the standard or heavy duty brakes in 75?

Re: rear brake drums
 

Doesn't classic enterprize offer upgrades for 71-2 rear brakes? Only thing is if you're keeping the 6lug you would have to have these redrilled or something.

Re: rear brake drums
 

They are the HD type and I was trying to keep 6 lug. Since the drums/discs were shot on the 81 and I bought the 6 lug disc and was wondering if the 81 6 lug 4x4 drums would fit the 69 axle with 81 2wd backing plate.

I would rather not redrill the drums since I need new ones.

Re: rear brake drums
 

THERE WAS NOTHING SPECIAL ABOUT THE 75. I THOUGHT THEY WERE ALL 2 5/8" WIDE IN LATER YEARS. IT WAS A NATURAL PROGRESSION OF BRAKE SHOES. I KNOW MY 82 1/2 TON HAS 2 5/8" WIDE SHOES & IT IS NOT A HEAVY DUTY MODEL & DOESN'T HAVE EXTRA HEAVY DUTY BRAKES. :hm: JOHN
EVERY 2WD 1/2 TON AFTER 1970 HAD 5 LUGS.