- Do It Yourself Auto Repair
Brake caliper drag sticking overheating.
Brakes - what a drag
This article will talk about a pattern failure on some cars and trucks that still seems to catch people by surprise. You have a vehicle with dragging front brakes. After a stop when you release the brake it takes a second or two before it starts to roll. You go through front brakes like they were free. On a long drive you can smell the brakes overheat. Brakes may shake after driving for 30 minutes or more. Your front rotors have that nice gunmetal blue look. Even with every new part you ever heard of the problem persists.
I first encountered this problem when I was working at a fleet garage and there were a lot of Chevy vans. Certain vans would eat brakes, mostly the older ones. One day I noticed the vans that ate brakes would also not gravity bleed from the calipers. So I took the brake hose bolt off the caliper and still nothing. I took the brake hose off the truck and sure enough here comes the fluid rushing out of the metal line.
I was unable to blow any air through the brake hose. Upon close inspection the wrap-around bracket that bolted to the a-frame to hold the hose had rusted inside and it was squeezing the hose effectively turning the brake hose into a one-way valve. Brake hydraulic pressure into the caliper becomes trapped.
Then I went over the the other side which had the same problem and I figured out if I spread the bracket open a little it would loosen its grip on the hose and allow fluid to flow.
Once I learned this little trick I was able to restore normal brake life to the entire fleet. Now when I see a brake hose with a wrap-around bracket I always give it a little to tweak to open it a bit.
I was reminded of this today because 93 Buick Park Avenue came in from another repair shop with all brand new brakes and they would start to stick on the freeway after a long drive and the other shop was out of ideas. The only old parts in the brake system on the entire car were the hoses and brake lines. They had even replaced the power brake booster. I fixed the car in 10 minutes with a flat blade screwdriver. You will also see this fault on Chrysler vans like Caravan, Voyager and Town and Country.
Most every wrap-around metal brake hose bracket can be spread open with a screwdriver, releasing the grip of the trapped rust inside. Normal brake operation returns when the brake fluid can easily flow in both directions.