1972 B-body with 4 wheels drum brakes.

-Completely replaced in 2008. All wheel cylinders, hardware, shoes, lines, hoses, etc.
-No problems the last 2 years. Pulled it out of storage this year and now I have the problem.
-Front brake hoses were leaking at the wheel cylinder this spring. Tightened them and they don't leak anymore.
-I'm running Dot 5 fluid that has turned yellow, but from the info I've found this is normal and not a problem.
-I've bled the front brakes, there was no air in the lines.
-I've adjusted the shoes out so they barely drag on the drums.
-I've switched tires side to side.
-After driving it for a while the problem goes away, then the right side heats up and pulses like a warped rotor.

I've run out of ideas. What else should I check?

Open up the left side and see if anything is not kosher and take the right drum in and have it checked for warpage

I once had trouble with a sticky rear drum on my pickup because the glue under the brake pad partially let go so the pad material would grab the inside of the drum and bunch-up all the sudden. I could see something like this causing all sorts of fun on the front end of something.

The second time I had a pulling problem was when I ended up with a weak front shock on one side which caused the truck to nosedive/lean to one side just enough that you had to steer it while applying the brakes. There was nothing wrong with the brakes, but it sure felt like it.

I've removed both drums. I did find a problem with the adjuster cable on the left side, it was pinned behind the guide. I fixed it, then ran the adjuster out just enough to get the shoes to drag on the drum.

Then I went to the right side, removed the drum and ran the adjuster in so that the wheel moved freely. Took it for a test drive. The pedal felt firmer, but it still pulled right.

Let me add that at the same time the brakes where done the whole front suspension and steering system was rebuilt. New tie rods, ball joints, shocks, and bushings. The front end is tight. Tires where also new at the time. I also checked tire pressure. Both tires are at 35 psi.

I'm wondering if one of the drums has been turned a little more than the others?

Have you checked the wheel cylinders? Sounds like the left side is maybe stuck.

Wheel cylinders were both replaced with the rest of the brake sytem. Both looked fine when I took the drums off. The left one must be moving or I wouldn't have gained firmness in the pedal when I adjusted the pads out.

The oddest part of the problem is that it goes away after you drive the car and use the brakes a few times. Then a little while later it develops a vibration from the right when braking.

Note that I have driven this car the last 2 summers on the current brake job without any issues. This has only been a problem since I started driving it this season. So something happened during storage over the winter.

holler back tomorrow as we're missing something, it should not be pulling to either side even for 1 or 2 stops. The side opposite the side it is being pulled to is not doing enough braking for some reason

It was pulling right at first, but not nearly to the extent that it was, it was a very, very slight pull. In fact I'm not even sure that it wasn't just my mind telling me it was pulling because that's what I expect out of it now. If that makes sense.

But I agree, I'm still not 100% convinced I've fixed the root problem. But, I definetely did fix a problem. After watching the left brake with the drum off it was obvious that the left adjuster was not functioning properly. This is also reinforced by how the brake pedal feels now.

I'll get it out on the road sometime today and I'll post the results.

Took it up the street earlier today and it still pulls right for the first 2 stops then it seems to be fine. It's much better than it was, and I think I did fix one problem, but there is still something wrong. I do have a brand new pair of brake hoses sitting on my work bench, maybe I should replace those and see what happens?

I was thinking about this today and my 1st thought yesterday was that maybe the contact pads were hanging up the inside edge of a shoe but then I remembered that it happened IN STORAGE and that made me think what a prior poster posted which was a wheel cyl got rusty a bit while sitting possibly from a bit of water sitting unmolested in the bottom of the bore. How does this sound: grab a new pair of cotter keys and pull the drums again and you press the brake a bit (not too far as you know you dont want the cups to come out) and 2 helpers on each side and have them tell you if both sides are moving (at the same time and equally) AND you hit the brake hard (er) w a block of wood under the pedal to as above to limit it's travel and see if either of these 2 tests make anything abnormal show up at the shoes

you have a lazy left front wheel cyl, it's not that its not working,its slow to respond.the right side comes on sooner than the left so it pulls right. change the left cylinder and you will be good. jeff57....by the way i own a brake and muffler shop...

Since the pull isn't anywhere near as bad as when I started, and it seems to go away after braking a couple of times, maybe I'll just drive it the way it is for now and see if the left wheel cylinder comes back. If it doesn't in a few weeks than I'll order another.

For what it's worth I've had both shoes and drums cause a pull. Even with a very nice finish on both drums that were cut to the same diameter. Switching the shoes or drums from side to side moved the direction of the pull. I would agree in your case to check the wheel cylinders,shoes,and drums since the pull goes away with use or temperature change. I would eliminate suspension,tires,return springs in your case. Another factor over looked are the backing plate pads. I have welded grooved plates and caliper mounts where they are worn.
Doug

Problem solved!

Saturday I ordered new shoes and hardware from Rock Auto and they finally show up on my porch yesterday. So last night did a standard brake job. Long story short, the left side shoes were contaminated. There was some sort of a black substance (looks like wet brake dust) along the edge of the shoes and along the edge of the backing plate. I suspect that this is brake fluid (from the previously mentioned leaking hose) mixed with brake dust. This wasn't easily visible until I actually removed the shoes because the backing plates are black and my garage isn't well lit. That's why I didn't see the problem simply removing the drum.

Anyway, I cleaned the drum surfaces, cleaned out the backing plates, then replaced the shoes and hardware. No all is fine and the car is braking even.

I was pretty busy last night because I had to do some maintenence on my DD for a road trip this weekend so I didn't get a chance to snap pictures. I will try to add some next week.