front brake locking up

[cknadroj]

92 Le Sabre with ABS

Bought this car a couple months ago from my father in law who bought it new. It has always had excellent care and is in fine shape. Among other things, it had new rotors and pads two years ago - maybe as many as 20,000 miles since. Almost 140,000 on the clock now.

However, the brakes on driver's front wheel seems to be locking up. The wheel got hot enough driving home from work to melt the plastic threads that hold the hubcap on and it feel off in my driveway.

I lifted the front, put transmission in neutral - the passenger side wheel spins about a full turn with a good push - the driver side will hardly turn. I took the caliper off, and the axle turns fine. Put the caliper back on, mashed the brake pedal - locked again.

I'm thinking of just replacing the entire caliper with a remanufaftured one. I've done plenty of rotors and pads on other vehicles before.

Has anyone seen this particular problem before? Is there anything I should know about ABS. Could the ABS be causing the problem?

Thanks

[Gocart879]

if the caliper hardware is/was not properly lubricated it will eventully result in a wheel(S) locking up. if you remove the wheel you will see a caliper slider usually surrounded by a rubber boot. it needs to be greased check your auto parts store for more details as they sell a specific grease just for the calipers.

[HotZ28]

I agree with Gocart, however, you could also have a caliper binding, quite common on 15 year old cars. If you do find it to be a caliper, replace both of them and flush all the old fluid from the system.

[cknadroj]

OK, I've lubed the sliders with the correct grease. The situation is better, but not fixed.

I drove the Puick about ten miles yesterday. Everything was fine for about five miles, then the brakes started acting funny, like a badly warped rotor. When I applied the brakes, they seem to grab/release, grab/release repeatedly (liked a warped rotor). When I got to my destination, the wheel was a lot hotter (too hot to be normal) on the driver side than the passenger side. Maybe the left side is still dragging some?

Situation is better though, as the driver side does not seem to locking anymore. It seems weird to me that it would simply be a warped rotor, even though it got hot enough to melt the hubcap plastic - seems like a warped rotor would be felt all the time rather than after a few miles.

What next?

[Gocart879]

well, if the driving is not chewing up brake pads in your 20 mile trips, or really getting too HOT, i would continue your trips. perhaps the shuttering and shaking will get better. after a good 100 miles, i think its time to say replace the rotors, and just as another check, pull the drivers side off again and make sure it seems to be working ok, have someone step on the pedal and observe, obiously when the engine is running(dont move the steering wheel)

[Flatrater]

Jack your front end up off the ground while the brake is locked up. Now open the bleeder screw on the caliper. If the wheel starts to move you don't have a caliper problem. Collapse the caliper piston into it's bore and move the caliper in and out that will show you don't have a slider issue. Only thing left to check now is the hose going form the metal line to the caliper. I would recommend changing that hose and bleeding the system. If the rubber hose is collapsed inside itself then you will get this type of problem.

[HotZ28]

If your rotor got hot enough to melt the hub cap plastic and also was driven in the rain, it is warped. After a rotor gets warm, it will show more signs of warping. Rotors are cheap, why not just replace them also.

[cknadroj]

Flatrater, you got it - it was the hose.