Drum brake adjustment?

TWEBB101

MEMBER
1984 CHEVROLET TRUCK
7.4L
V8
2WD
AUTOMATIC
172,500 MILES

I replaced all of hardware and brake shoes on both rear drums. I can get the wheels adjusted so that there is barely some drag, but then after a couple of drives, one or both of them are adjusted so tight that the brakes are burning and you can't spin the wheels by hand in neutral. After each adjustment, I do several reverse-stop procedures, trying to make sure everything is self-adjusted right, so I'm not sure if that is what is causing them to get so tight, or if it's something else. This "cycle" has happened several times over the last few months, since I replaced them.I loosen them, adjust them, drive it, and then they're tight again.

Have you seen/heard of this before?

Wednesday, December 17th, 2025 AT 2:19 PM

1 Reply

CARADIODOC

MECHANIC
34,363 POSTS

Actually it's quite common, but the cause can be elusive. With the drum off, look at the "parking brake strut bar" between the two shoes, right below the wheel cylinder. You'll see there's an anti-rattle spring on one end. Use your thumb to push against that spring. The bar should move a good 1/8th inch. If it's tight, look at the parking brake lever attached to the back of the rear shoe. That should be fully retracted so it's hidden from sight behind that shoe frame. It's most likely pulled forward due to a stuck parking brake cable. Another clue is that lever will move forward and back as you flex the parking brake cable right behind that brake assembly.

If the parking brake cable is just sluggish, use a large pry bar to retract the lever. At that point the play in the strut bar should return. If this doesn't help, post a photo of one of the brakes with the drum removed.

If it does help, do not try to lubricate the sticking cable. It must be replaced. When performing safety inspections on trade-ins at a very nice new-car dealership, we were only allowed to replace parking brake cables, or cut them. Cutting them was legal as long as it was disclosed on the window sticker. Even if lubricating them appeared to get them working properly, it was well-known that vehicle was going to come back sooner or later on a tow truck with a stuck cable.

If that strut bar is tight, also look at the anchor pin on top. Both brake shoes must be against that pin. If the parking brake is stuck partially applied, one or both shoes will be held away from that pin. When you push that shoe up to the pin, it will cause the other shoe to move away.

This drawing is of a different design, but the parts I described are the same as yours.

Image (Click to make bigger)