Right front brake caliper sticking - SOLVED 10-24-19

[vanagon40]

My OEM pads wore out after 20,500 miles.



I bought 4 sets of pads (eight pads total, or enough for two complete brake jobs). The first set lasted 22,500 miles and wore evenly (no pic).

BUT, I wore out the right pads on the second set in only 8,300 miles.



Each time I changed the brakes, I cleaned the pistons prior to compressing them. The right side compressed today enough to remove the caliper without undo pressure.

Would you recommend just expanding the pistons and cleaning them, or should I disassemble the caliper? Obviously, the right side is dragging.

[hubcapsc]

If you use hydraulic pressure to push the pistons out, clean them, and then
push them back in with just the strength of your fingers, you can make
a judgement call on how hard they are to push all the way back in.

I've though they were notably easier to push all the way back in after
removing the calipers, cleaning everything and putting in new seals.

If you think they're hard to push all the way back in and you're worried
that one might be sticking during use, maybe you'll decide to take
the whole thing apart...

-Mike

[da prez]

  If you push them out that far , s touch of brake fluid on the outside of the piston before you push them back in. Wipe off any excess and go for it.

                                  da prez

[Ricky-D]

The uneven wear on the pads indicate the problem is the "floating" part of the caliper.

The caliper is not properly "floating" as it was designed to do.

It's dirty and sticking and is not being allowed to properly seek it's neutral position.

That's your problem.

Not only that but because of your problem, you've probably have worn the rotors unevenly also.

And that cannot be corrected except by replacing with new rotors.

Which is what a consciencence rider would do, who worries about that stuff.

***

[vanagon40]

The uneven wear on the pads indicate the problem is the "floating" part of the caliper. . . .

The brake pads wore evenly on each rotor, it was just that the pads on the right rotor wore out prematurely. That does not seem to me to indicate a "floating" problem. Maybe I'm missing something.

Or maybe I did not explain the problem clearly:

[Highbinder]

I would recommend that you rebuild both calipers and clean the floating assembly,  clean and re-grease.  The pistons have 2 seals on each piston if one is compromised it wouldn't allow the piston to fully return, if you do decide to rebuild, make sure you clean the grooves where the seals go because there is usually a lot of corrosion build up in there..The reason I say to rebuild both is because you should be getting more then 20,000 out of a set of brake pads.

[Valkpilot]

The uneven wear on the pads indicate the problem is the "floating" part of the caliper. . . .

The brake pads wore evenly on each rotor, it was just that the pads on the right rotor wore out prematurely. That does not seem to me to indicate a "floating" problem. Maybe I'm missing something.

I think RickyD is right.  It's not just the pads that move, the whole caliper is supposed to slide back and forth on the caliper mounting pins.  If it is stuck in place, the pads will wear prematurely.

I had this problem on the rear brake, but instead of worn pads, I couldn't get the caliper back on the disk after a pad change.  It was stuck too far to one side.

[vanagon40]

I think RickyD is right.  It's not just the pads that move, the whole caliper is supposed to slide back and forth on the caliper mounting pins.  If it is stuck in place, the pads will wear prematurely. . . .

As I responded to RickyD, maybe I’m missing something. But you will have to explain this to me.

The identical wear to the inboard and outboard pads tells me the caliper was exactly centered over the rotor during the entire life of the pads–the caliper was moving freely.

If the caliper was stuck, I would expect the outboard pad would show substantial wear (the pistons pushing the pad against the rotor), while the inboard pad would show little to no wear (the pad frozen in place on the stuck caliper).

This is not rocket science.

Both pads showing the same excessive wear tells me the caliper is not completely releasing. In my experience with cars, this is caused by a either a defect in the caliper, or a defect with the flexible hose to the caliper not allowing the brake fluid to flow freely.

Unfortunately, I allowed family commitments to hinder my progress on this project. I have ordered new seals and will clean the calipers.

[vanagon40]

When I am wrong, I will admit being wrong. As suggested by RickyD and Valkpilot, the right caliper was not properly "floating" as it was designed to do. The slider pin was covered with rust and it took a few taps from my ball peen hammer to convince the caliper to separate from the mounting bracket.



Removed the rust, cleaned and rebuilt the calipers, and reinstalled with new pads and healthy dose of lubricant.



I still am troubled by the phenomenon that both pads wore evenly, but there is no doubt the excessive wear was due to the stuck caliper. I owe RickyD and Valkpilot an apology as I rejected their absolutely correct diagnosis and advice.

But I am finally back on the road.

[My prior post with the same information was deleted in the recent technical difficulties. I wanted to post the solution for anyone searching the same problem.]

[Valkpilot]

Glad it's fixed!