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-   -   Squeaking over bumps after swapping rotors/pads? (https://www.ft86club.com/forums/showthread.php?t=109117)

Captain Curt 08-02-2016 01:46 PM

Squeaking over bumps after swapping rotors/pads?
 
I recently replaced my rotors and pads with slotted rotors and CarboTech XP8 pads. After installation, my front passenger area makes a squeak over bumps and the entire car makes a loud squeaking sound when high reving to get up my driveway. I'm not sure if it's clutch chatter, or something else with the drive train/suspension. I should note that I did not have a dial indicator, so I wasn't able to test the new rotors for the best position on the hub. Is this possibly my issue?

Mr.ac 08-02-2016 10:30 PM

Wut?
Dial indicator? ...... All you did was rotors and pads right?
My guess, you didn't tighten down some bolts. Re torque every bolt. Double check the pad shims are holding the pads nice and snug. Check the dust shields, those could be rubbing on the rotors.

Unless you did more than just pads and rotors you have to tell us. I can't read minds at the moment so it's a guessing game till then.

Captain Curt 08-03-2016 06:52 PM

Quote:

Originally Posted by Mr.ac (Post 2719671)
Wut?
Dial indicator? ...... All you did was rotors and pads right?

Yup, all I did was replace rotors and pads. I thought at first maybe it was because I didn't have a dial indicator. From what I've heard you need to use one like this to find the least out-of-round position between the five possible locations, since the wheel hub and inner drum of the rotor may be out of round.


Quote:

Originally Posted by Mr.ac (Post 2719671)
My guess, you didn't tighten down some bolts. Re torque every bolt.

You hit the nail on the head. Yesterday my caliper on the front-passenger fell off after going over a bump :eyebulge:. The bolts that attach the caliper to the caliper slide pins came out some how. Not sure if I forgot to torque them to spec, or if my torque wrench is out of calibration, but it has since been garaged. Unfortunately after re-torquing the bolts the noise issue is still there.


Quote:

Originally Posted by Mr.ac (Post 2719671)
Double check the pad shims are holding the pads nice and snug. Check the dust shields, those could be rubbing on the rotors.

Double checked, all good those areas. :thumbsup:


Quote:

Originally Posted by Mr.ac (Post 2719671)
Unless you did more than just pads and rotors you have to tell us. I can't read minds at the moment so it's a guessing game till then.

I should note that the car has an ACT 6 puck clutch, garrett gt2867R turbo, upgraded fuel system and kw v3 coilovers. Not sure if they come in to play, but perhaps they may.

Tcoat 08-03-2016 08:22 PM

Quote:

Originally Posted by Captain Curt (Post 2720403)
Yup, all I did was replace rotors and pads. I thought at first maybe it was because I didn't have a dial indicator. From what I've heard you need to use one like this to find the least out-of-round position between the five possible locations, since the wheel hub and inner drum of the rotor may be out of round.




You hit the nail on the head. Yesterday my caliper on the front-passenger fell off after going over a bump :eyebulge:. The bolts that attach the caliper to the caliper slide pins came out some how. Not sure if I forgot to torque them to spec, or if my torque wrench is out of calibration, but it has since been garaged. Unfortunately after re-torquing the bolts the noise issue is still there.

.

Unless you are driving some million dollar supercar the little bit a rotor will be out of round will never be even slightly noticeable. The manufacturing specs on rotors is measured in decimals of mils (1/1000 of an inch) so any deviation is way too small to be noticed. Anybody that says you need a gauge on a street car is a pretentious goof.

Signed,
A guy who works where 5 million rotors a year are made.


If the bolts cam out not only were they not torqued they were not even tightened. Go back over everything and check again. Or better yet take it to a shop and have them check it over. A caliper falling off while driving is not a small matter.

Mr.ac 08-03-2016 09:16 PM

Right on, well you if your caliper fell out then things are not tight enough. I say give your torque wrench an extra 10-15lbs.

Ah coilovers, yeah common problems are sway bar endlinks coming loose or the sway bars themselves. Again all due to loose bolts/nuts.

The loud squeaking at high revs, could be a slipping belt.

If possible a video or audio clip would help out.

Captain Curt 08-04-2016 09:56 PM

Quote:

Originally Posted by Tcoat (Post 2720467)
Unless you are driving some million dollar supercar the little bit a rotor will be out of round will never be even slightly noticeable. The manufacturing specs on rotors is measured in decimals of mils (1/1000 of an inch) so any deviation is way too small to be noticed. Anybody that says you need a gauge on a street car is a pretentious goof.

Signed,
A guy who works where 5 million rotors a year are made.


If the bolts cam out not only were they not torqued they were not even tightened. Go back over everything and check again. Or better yet take it to a shop and have them check it over. A caliper falling off while driving is not a small matter.

Good to know it makes no difference, that's one thing I can eliminate. As for going back over everything, the car has been garaged and I am pulling all four wheels off and double checking everything. Unfortunately when I did the work I had a distracting family member berating me and I must have forgotten to torque down the caliper bolts on that wheel. I hand tightened all four wheels then went back with the torque wrench and must have forgotten this one. After re-torquing everything I'm taking it to the shop to have it double-checked. I'm still new to this and having a professional take a look at my work is something I should have done from the start.

Captain Curt 08-04-2016 10:00 PM

Quote:

Originally Posted by Mr.ac (Post 2720503)
Right on, well you if your caliper fell out then things are not tight enough. I say give your torque wrench an extra 10-15lbs

Definitely going to over torque everything and have the wrench calibrated. I honestly think that what happened is I done goofed and forgot to do the final torquing on those two bolts.

Quote:

Originally Posted by Mr.ac (Post 2720503)
Ah coilovers, yeah common problems are sway bar endlinks coming loose or the sway bars themselves. Again all due to loose bolts/nuts.

I'll take a look when I pull the wheels off again, but when I was down there everything looked good.

Quote:

Originally Posted by Mr.ac (Post 2720503)
The loud squeaking at high revs, could be a slipping belt.

I think it's not a belt-related issue since the sound is more like two pieces of metal rubbing. That's the best way that I can describe it. I checked all the belts and everything is good.

Quote:

Originally Posted by Mr.ac (Post 2720503)
If possible a video or audio clip would help out.

I'll try and get a video this weekend when I have time to diagnose, it may be hard since the car is extremely loud but it's worth a shot.


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