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High pitched squeal...

Coming from the drivers side on a long road trip last weekend. A little background for ya, 75 914 new front brake pads 2 weeks did not turn the rotors at that time thanks to rain but intend to shortly. This was a persistant squeal (we're talking a couple hours) that only started after running at 75mph for about 15 minutes it would also go away as soon as the car was stopped and not start again till that speed. I pulled the wheels and checked the rotors for free play and found none, nothing between the pads and rotor, and the hubs were not hot around the bearings... I'm stumped! I wasn't able to do anymore dedutive work because the factory jack FAILED! Glad I wasn't under the car or anything... any way a little help from the veterans would be great.
Old 04-01-2005, 11:47 AM
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Just some thoughts:

Its the noise definately coming from the front? You could possibly re-create the noise if it were coming from the rear by jacking up the car & running it up to 75 (carefully blocking the wheels & jackstands).

If definately the front, how do the wheels turn when jacked up? freely, or with some resistance. Could also be front bearings but sounds like it is related to the brake job. Does the car pull to one side?
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Old 04-01-2005, 03:17 PM
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When you replaced the front pads did you use anti-squeal goo? Not sure of the proper name. And are the metal pieces behind the pads in properly?

I've put them in wrong before, as I'm sure others have too.

The noise could be speed related in the front, it just takes 75mph to set up the right harmonics that close to the hub. Just like it takes 50-60mph for a wheel to 'vibrate' that is out of balance at 8 inches from the hub(well 50 -60mph on my car).

Catch my drift?
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Old 04-01-2005, 03:48 PM
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Thanks for the quick responses guys, no time this weekend to work on the car... maybe tonight. Tidybouy- that's a good idea I'll give that a shot this week. Conrad- if you are talking about the piston retention plates then yeah I am pretty sure those are in right.
I am leaning toward the rotors as the problem but we'll see, I will do the bearing at the same time and update you guys, thanks again.
Old 04-04-2005, 09:51 AM
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Lose the jack....it was made for road side emergencies.......it was a limitted use piece of crap 30 year ago..time has not helped it.

Squeals while running have not much to do with brakes...sounds like a bearing....squeals with brakes should only happen with brakes are applied....which means metal on metal....obviously not since you have new pads....or lack of anti squeal behind the pads....
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Old 04-05-2005, 08:36 PM
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I agree Mike which is why I took a long hard look at the wheel bearings when I pulled the rotors. They look fine to the naked eye but they are being replaced today regardless. I will update you guys as soon as I get it back on the road.
Old 04-06-2005, 08:24 AM
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Another thought:

Maybe since you didn't turn the rotors but put on new pads, is it possible that the rotor had some wear that is now having pressure applied by the new (true) brake pads and that is adding pressure to the wheel bearings? What was the condition of the old pads? the wear pattern could indicate the shape of your rotors.

Just my 2 cents worth...
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Old 04-06-2005, 07:49 PM
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I had a similar problem last year , caused by similar situation.
After replacing the bearings to no avail, I solved the problem with liberal application of CRC anti-squeal goo ( the orange stuff you can get at autozone or other flaps) to the thin anti squal shims that are installed behind the pads. After 8 k no more squeal .
Bill
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Old 04-07-2005, 03:55 AM
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OK small update for you guys. Turned rotors and new bearings put on last night, flushed the brake lines (unrelated to the squeal but a good idea none the less) and did a quick spin around the block. No squeal as of yet but again it didn't happen until I ran 75 for a little while so we shall see, if the rain stops (isn't this California?) I will go for a nice long drive this weekend and let you guys know what's up. BTW Mike I was using the stock jack because I was about 5 hours from my shop when the noise came on, any ideas about a replacement for the random emergency that may come up? Thanks again for all the help.
Old 04-08-2005, 10:10 AM
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As for a jack.. I got a scissor jack from a wrecker for $5.00 and it fits inside the spare.

Along with a spare clutch and throttle cable, of course.
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Old 04-08-2005, 10:42 AM
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Ok, finally an update for you guys that have helped me out... after replacing the front bearings, turning rotors, and squeal goo-ing the pads.... the noise is BACK and worse! Coming from the rear for sure at this point. I bought this car from my brother and it's sat for the most part for the last 5 years or so, so I am thinking rear wheel bearings at this point. Anyone else ever try the DIY rear bearing job that is posted in the Tech section here? I don't mind paying for a shop to do it but I hate paying another person for something I can do myself.

Any more thoughts for what this noise might be at this point? Again thanks in advance for the help.
Old 04-17-2005, 09:59 AM
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Pretty much all the same types of things. Mostly related to the brakes...

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Old 04-17-2005, 11:20 AM
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Are you thinking brakes even though I haven't done anything to the rears? I'll do the rear pads and turn the rotors now and see where that leaves me. I'd much rather do brakes than mess with a bearing issue. I am wondering about a constant noise being brakes though... that sounds more like a bearing, unless the venting clearance is wrong or maybe a sticky caliper?
Old 04-17-2005, 03:10 PM
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Prety easy to tell on the rears if they are dragging. With the proper venting clearance they should still turn without dragging or squeaking.
The rear bearings if bad will sound bad if you turn the wheel while up on a jack stand. It will be a rumble grind noise.
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Old 04-17-2005, 05:15 PM
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My car sat parkled for a year and a half and the rotors got fairly heavy coat of surface rust. They made noise like they were dragging but after several drives, everything smoothed out.

Maybe you could goe for a spin and apply the brakes several times to clean off the rotors.

Vern
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Old 04-17-2005, 06:45 PM
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Allright got the car up on stands last night (wish I didn't have to work for a living) and I noticed that there was drag on the rotors from the pads... must be my noise right? There should be no drag with the proper venting clearance correct?
As a side note what is a good solid location for a jack stand? Somewhere on the longs?
Old 04-20-2005, 07:52 AM
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With the venting clearance properly set, you should have very little if any drag on the rear wheels from the brakes. Sounds like you might need to set the clearance. We have the procedure in one of our tech articles... I personally prefer the feel of the brake system with only half of the stock specified clearance. YMMV, but the amount of clearance does affect the feel of the brakes.

You can put a jackstand on the "donut" on the floorpan, at the front corner of the engine bay on the triangle-shaped reinforcing piece. Or if that is gone, on the longitudinal where it turns to go upward to the rear shock mount. Or, especially with the stands whose top end is shaped like a curvy bracket ( { ), you can put the center of the bracket on the trailing arm's pivot.

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Old 04-20-2005, 09:42 AM
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Thanks Dave, I have been using the donut but I will try the trailing arm also. I've checked out the tech article, I think I've read all of em at one point or another... this site is GREAT! Keep up the great work for us newbies. Thanks again.
Old 04-20-2005, 09:59 AM
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If the brake idea does not pan out, and the bearings appear to spin smooth, then I would suspect the grease seals on the bearings are old and dry. These are the plastic rings on each side of the rear bearing and they can make noise once the axles are rotating fast enough. Unfortunately you can't get at them unless you remove the stub axle and hub, and chances are the bearings and races will be damaged in the removal process anyway.
Old 04-20-2005, 10:04 AM
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UPDATE UPDATE UPDATE
The drivers side rear rotor was TOO warped to chuck up in the lathe... must have been my noise (I hope)

New question at this point about venting clearance. How much tension should be on the feeler gauge at the proper point? Slight drag all the way to the hub or do you only go in an inch or so?
Old 04-21-2005, 08:33 AM
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