Hmmm...this can't be right

[wxman1]

I'm driving a 69 C10 P/U with a 350/TH350.
Drum brakes all around of course. I have
re-done the front end. New ball joints, new
bearings, new drums and brake shoes are
about 3 months old. I've noticed an oscillation mainly in the right front during braking. I jacked up that wheel, and when I spin it...it seems the brake shoes drag more at one point. It is noticeable but not really bad. I
checked the drums for out of round as best I could...they seem OK...but how much out of
round is to much? The only "old" parts that got re-used were the backing plate and the hubs.
I even changed out the brake cylinders on the wheels.

Has anyboby ever had this problem? This is
the first vehicle that I've driven since 1979 that
had drum brakes all around. Is this just typical
of problems with drum brakes? Is the only
permanent solution to get the disc brake
upgrade kit??

Jim
Mt Juliet

[truckster]

Just off the top of my head, the interior of the drum should be perfectly round after it was turned (last step of the manufacturing process). I have a couple of theories that might cause one to be slightly out of round-

1. a drum was dropped on its edge after it was turned.

2. a drum wasn't perfectly centered on the arbor when it was turned.

The only way I can think of to be 100% sure they're round is to put them on a brake lathe to check them.

[Truckhead]

Sounds like an out of round brake drum. If you need brakes you can have mine for free. I'm located in Virginia.

[swb70]

I agree. Go have them returned. They should be perfetly round.