deep dish brake drums?

[buickracing]

Hi folks,
a new guy here.. I just acquired my grandfathers original '68 GMC C-10 (camper special?).. I've been improving/upgrading it including installing a fresh 327 I had, rebuilt TH-400 with shift kit, completely rebuilt the drum brakes.. which leads to my conundrum. (pun)..
The rear drums are the standard 6-lug, 2inch by 11 inch standard on most 1/2 tons as far as I can tell. The problem is that MY drums have an axle-mounting flange that is roughly 1/2 deeper than every single replacement drum I find. (i.e., if you lay the drum flat on a table, the center of the drum height is 3.5 inches instead of the usual 3 inches.. In other words, my axle shafts appear to be 1/2 inch longer than stock, and the drums therefor have a 1/2 inch bell shape which correctly locates the drum surface over the two-inch shoes. Its killing me.. I've gone through many websites thinking that perhaps the dealer installed a rear-end from a different truck (k-10, 2-20, suburban, van.. etc.) .. but none of them seem to be like the rear end I have (leaf-spring, 10-bolt, 3:55 rear)..etc.. has anyone else seen this? Or know what is going on here? The thought of getting custom axles, or a new rear end because I can't find a couple of $25 drums is too much!.
Thanks in advance,
Barton

[Sammy]

Get out your tape measure and your camera take a few pics of your setup. Someone should be able to point you the right direction and possibly get you the part numbers you need. Personally I was at the understanding there were two types of brakes/drums used the narrow drum and the wider drum you are referring to.

[chewychevy67]

you must have the dana 44 rear differential. I believe only |GMC had these put in there trucks but could be wrong. i have the same in my 67 GMC. I had a very hard time finding new drums for mine? Does it look like this one?

[70cst]

Originally Posted by Sammy

Get out your tape measure and your camera take a few pics of your setup. Someone should be able to point you the right direction and possibly get you the part numbers you need. Personally I was at the understanding there were two types of brakes/drums used the narrow drum and the wider drum you are referring to.

I believe you are correct. Then again I could be wrong.

Also... AND from Ohio.

[70cst]

Re: I'm confused about my trucks rear axle...
http://67-72chevytrucks.com/vboard/s....php?p=4019031

Check the above thread...it might help.

[raycow]

Buickracing, I think the explanation for all of your parts problems is "leaf springs". Every 63-72 leaf spring C-10 I have seen had a Dana rear, and apparently it is the same rear that was used by GMC. As you can see, the rear is quite different from a coil spring Chevy, for example, the pressed-on bearing. I believe that if you ask for 1/2 ton GMC parts they should fit. If your partsperson tells you "they are the same as Chevy", find another parts store. The catalogs for some lines show this and they are just plain wrong.

Please let us know how this works out for you.

Ray

[buickracing]

Hey guys, thanks for the replies.. in fact, the drum does look like the photo that chewy put in above. We may be on to something here! Thanks for the help!.. I've attached a couple of pics to share with the universe.. I teach high school here in California and rebuilt the 327 in my classroom in front of my students (during lunch hours and prep periods. Its great having teenagers around to scrub parts, clean threads, etc. To be honest, they did most of the actual work (cleaning parts, torquing bolts etc while I worked at my desk and directed them)..I'll follow the leads provided and get back to y'all! Thanks again.
http://drake.marin.k12.ca.us/staff/c...ct%20page.html

[Kit Maira]

Anyone know where I might find one decent drum like the one in the pic? It's an 11" drum, six lug with a 3.5" depth. For a Dana 44 rear end, 68 GMC. This is apparently not an auto parts store item. Thanks in advance.