Rear Drums and Brakes on 1974 Blazer

[Chief Brody]

I just wanted to swap a wheel out and ended up twisting off two lug studs...so that led to pulling the drum off...which led to now I need to redo the brake cylinder and parts...AND I have original GM drums and would like to keep them, but there is a groove in them...what are the chances that they can be turned and saved?

 

[diesel4me]

If they are still in specs (enough meat left to turn them )- but you'll end up with some of a groove after turning them to the limits,it "might" not be enough of a groove to cause braking issues ,although at first it'll take awhile for the linings to wear into the groove and "bed in"....or,it might end up leading to problems with the brakes locking too easily or grabby,in that case replacing the drums is best..once they are turned to the maximum diameter they are more prone to warping and cracking..

In the past when I worked at parts stores and had access to a brake lathe,I turned many of my drums down until the grooves were gone,and despite going a bit beyond the "discard" limits,I didn't have any trouble with warpage or cracking...rear drums dont usually do as much braking as the front ones and run a bit cooler..
I never towed anything though..

 

[Chief Brody]

Seems like somebody had a thread recently where they were saying that all new brake drums are crap and to save original GM if at all possible

Original GM are impossible to find at any price...not sure what I will do if they can't be turned

 

[diesel4me]

That is the curse of owning an old "antique" vehicle,parts might still be available,but only in aftermarket form,and the supply of OEM stuff has probably dried up long ago--any you might find still,will be priced accordingly..

Maybe you could find some OEM drums at an old dealership or a parts store thats been around "forever"--perhaps Rock Auto might have some oem ones they bought from a closed dealership or warehouse too..

Someone may still have some good Wagner,Raybestos or EIS brand ones hanging around..there were some salvage yards local to me selling new Raybestos drums from Canada that were good quality and they were often cheaper than what I could order from warehouses at the parts stores too..

Another possibility is a salvage yard--you may find a wrecked truck with low miles that still has the original drums on it..around here that would be a very slim possibility though !..

 

[Chief Brody]

Sandblasted the original GM Drums

 

[Chief Brody]

The Dirty mess these were so old they still had GM stamped on the core...I figure mid-80's?

 

[Chief Brody]

Lot's of cleaning, rust treatment, 6 new lugs and a headache later:

 

[Chief Brody]

New wheel cylinder with hardware cleaned and wire brushed. Copper anti-seize on the pinch points for the shoes

 

[Chief Brody]

All hardware back in place, parts cleaned and burnished...feeling good about now except hurting all over

 

[Chief Brody]

Clearcoated drums back on...I will wire cup brush that center piece when I take it back off this weekend to replace a spring on the self-adjusting arm that flew up and didn't come down and I couldn't find it

 

[Chief Brody]

I was so ticked that I could not find or buy a spring that I bought every one I could find on Rock Auto. They are old stock and Made in the U.S.A.

 

[livid4dirt]

Clearcoated drums back on...I will wire cup brush that center piece when I take it back off this weekend to replace a spring on the self-adjusting arm that flew up and didn't come down and I couldn't find it

View attachment 217053

So, you must have been able to have these turned? Your attention detail through out this build is amazing, kudos!

 

[diesel4me]

The Dirty mess these were so old they still had GM stamped on the core...I figure mid-80's?

View attachment 217049

They do look original to the rear axle (which might not be original to your truck,only way to tell for sure is to get the axle code off the tube if its still legible)...

Did you pull the axle to install the lug studs with a hammer ?--I haven't had any issues "pulling" then in using a lug nut and a collar,but some have had them not seat fully using that method and the lugs loosened up after a few miles--I'd check the lugs torque often the first few miles to ensure the studs are fully seated..

 

[Chief Brody]

They do look original to the rear axle (which might not be original to your truck,only way to tell for sure is to get the axle code off the tube if its still legible)...

Did you pull the axle to install the lug studs with a hammer ?--I haven't had any issues "pulling" then in using a lug nut and a collar,but some have had them not seat fully using that method and the lugs loosened up after a few miles--I'd check the lugs torque often the first few miles to ensure the studs are fully seated..

I used a lug nut installation tool which was worth every penny of $19.99 It has a bearing built in and makes it easy to install them and seat them firmly

 

[Chief Brody]

They do look original to the rear axle (which might not be original to your truck,only way to tell for sure is to get the axle code off the tube if its still legible)...

I do plan to look for that when I get under there again and can clean the axle real good

 

[Chief Brody]

So, you must have been able to have these turned? Your attention detail through out this build is amazing, kudos!

Unfortunately I was not able to have them turned so I am using them until I find a better set...they are working at 90% plus...they just won't squeal when the shoes are worn out...but that will be a long long time