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Wheel overheating after brake pad installation


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I have noticed that one of the wheels,  the metal part of the brake pads in the wheel, have been very hot after running after I changed the brake pads yesterday.  I jacked it up again, pulled off the tire and did not see that anything in the brakes was improperly installed.  What could go wrong in a brake pad installation where lines were not bled, it was simply a re-installation of what was taken off with the new pads after the pistons were forced back in?   There are no sound or performance issues but the metal is extremely hot to the touch after running for 15 minutes.

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I see that you're in New England somewhere and that means you're in the Rust Belt. Did you check and relube the caliper slide pins when you were doing brakework? 

 

Often in older cars and/or salted-road cars these sliders will stick and not allow the caliper to properly centre itself over the rotor where it should be. Were the old pads evenly worn when you took them out or was one much thicker than the other? This often indicates some stuck sliders.

 

Sometimes these things take a fair bit of working to get them freed up... Good luck whatever it turns out to be.

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Thanks for the response.  Yes, one of the sliders was stuck.  How important is it that they can adjust freely and not be frozen?  Thanks.

 

It's pretty important for those to move freely. They are what allow the caliper to push from one side and make even braking force on both sides of the rotor. Without even braking force you're giving up some of your braking performance as well as unevenly wearing components. This is something that definitely needs to get sorted out.

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very important - they can't be stuck.

 

you also need to tell us what model/year.

 

the newer...sometime around 2001-ish models have a STUPID IDIOTIC ASININE bushing (can you tell i've seen it happen a bunch of times?) on one of the two pins on each caliper.  this bushing swells and catches inside the bore.  it seems likely to happen after a brake job...exposure to elements, larger than normal range of motion, new grease, etc.  

 

anyway - the good news with this issue is that you can just throw the bushigns away, i do it as routine maintenance now they're so annoying.

 

if it's and older car or even new - it could simple be rusted. have a really good pipe wrench or other device handy, they can be a bear to turn and get to come out.  i've had a few that required torches they were rusted so bad.   clean up, properly grease and you're done

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If you find that the stuck slide pin isn't the issue, I'd bet on sticking piston in that caliper as the culprit.

 

When brake fluid isn't flushed out every 48 months and refreshed, particularly in salt and high humidity areas, water gets into the brake fluid. It settles in the caliper and forms rust around the caliper bore and the piston. Usually the brakes will work normally, but the piston doesn't get the chance to slide away from the brake pads completely when you take your foot off the brake pedal. One or both brake pads on that wheel exert pressure on the rotor, and hence the quick wear and heat buldup.

 

If this is the issue, you can remove the caliper from its carrier and have someone slowly push the brake pedal until the piston pops out. Its messy, be prepared. Clean the caliper bore and the piston with 0000 steel wool. If there is any pitting seen on either, replace the caliper.

 

If not, apply fresh brake fluid to both and carefully reinsert the piston back into the caliper, being careful not to cut the piston seal and dust cover. Obviously, rebleed the wheel afterwards. Good Luck!

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And if those weren't enough, some aftermarket pads don't fit properly, the metal backing is a bit oversize and the pad sticks.

 

agreed - if you had to force the pads into place in the brackets, they are not going to work properly. The pads should have a little bit of movement when installed in the bracket. If they are tight in the bracket they wont release the rotor properly, causing drag and overheating/premature failure.

 

If this was the case, try to determine where the pad backing plate is binding in the bracket, take it out and file the backing until it fits easily into the bracket.

 

Also, if the piston was not compressed evenly, it can also cause problems.

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