This problem is driving me crazy.

A year and a half ago I replaced the Wheel bearings, rotors, pads and passenger side caliper bracket. Also the driver side upper ball joint. It was braking like new for about 8 months then it started to shake again. Just a little at first but now its pretty bad.

I have narrowed it down to the passenger side. I have pulled off both sides and with the caliper off (1 side at a time) applied the brake. The driver side pushes right out but the passenger side it tight even with the caliper off the rotor.

If I open the bleeder the passenger side caliper piston pushes in smoothly, so does the driver. I tried replacing the flex line on the pass side but didn't help. There are no leaks in the braking system either.

I guess i'm down to the proportioning valve or the ABS pump (no ABS light). Anyone know what might cause this? Thanks



PS. The tie rods are fine. ball joins have small play but i'm sure it's from the shaking for months. I have bled the system several times and everything is grease up perfectly.

 

Not sure what you mean when you say the passenger side is tight.

 

To clarify: I took the caliper off (with the line still connected) and pushed the brake pedal. It felt tighter than it should and the caliper piston barely moved.

Also the inside pad on passenger side is more worn than outer one. Driver side is even.

 

Thanks for the clarification.

This sounds more like a sticking caliper piston vs something bad in the hydraulics. You said you replaced only the passenger side caliper bracket. Why? Did you also replace the caliper?

You could replace the piston and the square cut seal on the passenger caliper as long as the dust boot is in good shape. That would save you some money.