About 2 months ago, my brakes started groaning and vibrating. Over time this got MUCH worse. I could tell it was my fronts, so i pulled my drivers side front wheel off for a look. The pads looked a little worn but not bad, and everything else looked fine, so I bolted the wheel back on with the intention of doing a brake job soon.

However it didnt take long for the truck to become almost undrivable, so I pulled my right front to replace the pads and found this:



Obviously, the rotor is unbelievably destroyed. The outside pad is also worn away to nothing. Strangely, the inside pad and rotor surface are well worn but nothing out of the ordinary. The driver's side is still normally worn as well.

I had this wheel off just 2 or 3 months ago tops and everything looked fine. However about 8 months ago I had hit a cinder block in the road at about 50 mph, which bent my wheel into contact with the hub (I think) and also damaged the sleeve on one of my shocks.

I bolted on a new wheel, and straightened up the shock sleeve. I also removed my front driveshaft due to a binding once per rotation. I thought this binding was in the axle but now I'm not so sure.

By the way, this isnt the first time this side tire has taken a hard direct impact.

Needless to say its getting new rotors and pads. But I hate to see them destroyed this way too if whatever caused this is still around. Could it be a bent caliper? Warped rotor? Something to do with the backing plate? The caliper is a strong unit and looks normal. The backing plate is a little bent but not bad. Any ideas? Any help appreciated!

 

92 Bronco, 351w e40d. Dana 44 front w/ Dana 70 auto-locking hubs (retired state vehicle)

 

Given that this happened to the outboard side of the rotor, I would be looking closely at caliper mounting and/or the caliper itself. Heavy brake dust build up and other crud can cause the caliper to drag after release. And while the inboard (direct application) pad will retract with the piston, the outboard (secondary application) relies on the free movement of the caliper itself to keep the outboard pad from continuing to drag on the rotor once the pedal has been released.

 

I agree with Grey, most likely caliper is sticking inwards, moves in under all the hydraulic pressure, but doesn't move out after releasing brake.

All sliding surfaces need to be clean, no rust, nothing bent, sand/file if needed and use high-temp brake grease sparingly on all sliding surfaces caliper to knuckle.

If there are pins in rubber boots, both pins and boots need to be in good shape. Can lightly lube pins with the brake grease before installing in boots.

 

turns out the front plunger on my left rear drum was disengaged. The way weight and torque transfer tend to work i could definitely see this affecting my RF.

 

im inclined to agree with the other two posters. make sure the caliper moves freely. you said this wheel has been wacked hard twice, its possible you tweeked the spindle where the caliper mounts up. if it was caused by some kind of torque transfer the inner pad would be worn out as well.

 

I agree as well, just making sure I cover all my bases. I dont wanna have to destroy another rotor to find the cause.

My only other thought was maybe a defective pad. No way to know now though as its down to the metal.

Thanks everyone for your help I'll let you know if I find anything definitive.