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View Full Version : Brake noise after replacing rotors and pads


tballard
09-17-2008, 02:40 PM
(I apologize in advance, this is going to be a novel. I'm new here, be gentle...)

My wife's 2006 Saturn Vue (V6, FWD, with the 17 inch rims, ~38k) developed a nasty shutter in the front brakes. When she took it to the dealer, they told her the rotors were warped and pads needed replacing. Not under warranty. Of course they also told her her oil needed changing (2k miles since the last change), air filter was shot, cabin air filter was shot, and some other markups. Being no fool, she said, thanks, but I'll keep my $700 for now.

I'm mechanically inclined, but have never really worked on cars. Fortunately, the internet is a good teacher, and down at Autozone they'll sell car parts to any fool off the street. :)

And thus, my great brake repair odyssey started.

My first step was to jack up the car, pull off the old pads and rotors. So far, so good. I got a little surprise when I did the passenger side, in that the pads were not worn evenly at all. There was a definite slope to the pad of (I'd estimate) an 1/8". Yikes! This might explain the shutter and warp, I was a little concerned about what have cause the uneven wear, but decided to press forward under the following (possibly foolish) assumptions:

1. The boot on one of the guide pins had come loose, and that pin seemed almost bone-dry lubrication-wise. (This was the pin without the bushing on it)
2. The caliper seemed to slide freely, and the pistons didn't appear (to my untrained prodding) to be hung up
3. I wasn't about to replace the caliper, and wasn't going to put the old parts back on. If the caliper pressure was uneven, over time I would find out right?

So, I put on the new rotors and pads. The rotors are whatever Duralast part the Autozone guy thought was right when I told him the car's specs, and the pads were the "second grade" up from the bottom.

I did some "bedding in" and everything seemed fine, the brakes worked, the shudder was gone. Having read a bit more, I'm not sure I bedded them in correctly. I really only did a handful of 25-30 MPH to near-zero passes, and not very aggressively. There was a tiny squeak, but I figured that was part of the breaking in process, since I've had that before on other cars when the pads were professionally changed.

A week later, the squeak is still there, and getting louder. It's only when braking and doesn't appear to be localized to one side. (It's hard to tell with that sort of noise) It tends to occur towards the end of a stop. Because this is the car my wife and small child ride around in, I decide to play it safe and take it to a brake place to be looked at. $117 later, the car has been aligned, brake system flushed, and my work inspected. The verdict: "Everything you did looks great".

But the squeak persists.

While I was in the Brake shop, I had ample time to look over the gloom-and-doom pamphlet from a brake parts company that claimed you should ALWAYS change out your brake hardware when you change you pads. If you don't, you're going to die in a horrible fireball and be mocked for being so stupid.

Additionally, online I find better sources on bedding in, and a lot of places indicating that perhaps I should have used Brake Quiet. Fine. I'll try the Brake Quiet, because that's the easiest fix, and while I'm in there, I'll swap out the hardware to avoid the fireball of death.

Another trip to Autozone, and I leave with a 4 buck can of brake quiet, and a 7 buck bag of hardware. I get home and discover that the hardware doesn't fit. Not even close.

So, back to Autozone I go. It turns out their computer is wrong. No matter what you do, it recommends the hardware they gave me, which is clearly wrong, and they can't find another option. Damn. That's okay, the guy explains it's mainly heat fatigue which gets to the clips, and mine look fine. Don't waste your time.

Not wanting to give up, I ask if they have the ceramic pads in stock now. (They didn't before or I would have got them the first time, and hey, maybe it's just crappy pads, right?) Nope, they don't have them yet, but the Autozone down the road does.

Away I go, and soon have a fancy box with nifty new pads. The woman explains they have a patented anti-vibration rubber backing, and should be dead quiet. And, lo-and-behold, the pads come with hardware! (The clips at least) And it's the right size and everything! "So.... I don't need that spray on Brake Quiet," I ask. "Oh no... that's really only for older cars which don't have integral shims.... just use the grease" (Which I've since confirmed on threads here. Say what you will about service in America, but I'm pretty happy with Autozone so far)

Returning home, continue to work on the car's driver side, which is where I started. That goes fine. I go to the passenger side, and the caliper slide doesn't want to come off the pins. It's a bit stiff, and I have to give it a little "persuasion" with a short lever to get it off the end of the pins. Uh-oh... this doesn't strike me as a good thing. Perhaps the pins are messed up? Bent? Worn?

Closer inspection reveals the rubber bushing at the end of one pin is all soft and a little torn. I'm 80% sure that's when the major or the friction is coming from. I've seen something which looks like the rubber bit (referred to in several threads in this forum as "bits of licorice") in the original bag of hardware which didn't fit. Of course, the problem there is that Autozone doesn't have a set that fits. They've looked for me. At length.

Fine, I'll just buy new pins, that should help. Not wanting to race off to Autozone again, I try to look them up online. As near as I can tell, no one sells either the bushings or the pins. I've tried the online catalogs of Napa, Autozone, etc... Google is coming up empty too. Crap.

So, I fiddle around a bit, and convince myself that with a lot of grease, the slide is not that bad, particularly when the slide is fully on the pins. Let's try the new pads, and see if that helps. I put the new pads in the new clips, grease the heck out of the pins, the pistons, the back of the pad, the clips, and anything else I can find, and slap the wheels back on. (By now I've at least wised up and bought a floor jack, so I'm not cranking the car up and down as laboriously....)

I take the care out to the nice, brand new empty road a block from my house and do about 10-15 stops. 25 to 0, about 5 times. Perfect! Dead silent, and grip like crazy. 35 to 0, about 4 times. Perfect as well. 45 to 0.... wait.... what's that? "squeeaaak" Not loud, not as much as before, but definitely there. I finish another 4 or 5 of the 45 to 0 runs, it's still squeaking a bit. Crap.

I let the care rest, and take it on a short 4 mile drive, and yup, it still squeaks, and seems to be towards the end of the brake cycle, and doesn't (I think) appear to change depending on the rotors/pads being warmed up.

Soooooo..... now I have some questions:

1. Is it possible this is just the wonky bushing? If so, where can I buy a new one? Can I buy them from the dealer?

2. The voice in my head tells me to suspect the pins, and I'd like to replace them, but again, where do I buy them? Additionally, do they just unbolt? I did a little exploratory tweaking, and they seemed quite tight. (I'm not sure I can get enough torque on them when the caliper is loose, which disturbs me)

3. I used the entire packet of caliper grease which came with the pads. I had to stretch it a bit thin towards the end, should I use more? I've ruled out the original can of Brake Quiet, but should I use one of the synthetic Brake Quiet products?

4. Is it possible I glazed the pads or rotors? Would there be any point in taking some steel wool to them?

5. The only other variable I can think of is the caliper itself. Is there any way I can determine this without special tools? I'd really like to avoid disconnecting the brake lines as well.

I have pictures of the bolts from the first time I took the brakes apart, which I'll post in case they help. (I took a lot of pictures in case I needed a reference to put something back together)

Thanks for any advice in advance.

tballard
09-18-2008, 09:12 AM
Okay, I'm going to reply to my own message, just in it helps someone else in the future.

So far, I haven't found a local source, but I have found them online at RockAuto.com (http://www.rockauto.com), more specifically, DORMAN Part # HW5086 (http://www.rockauto.com/catalog/x,carcode,1432890,parttype,1712). (Unfortunately, the new bolts don't appear to come with the bushing, and I've had not luck finding that yet. I'm going to try calling the local dealership today.)

I've also uploaded pictures of the pins:

http://www.saturnfans.com/photos/data/500/thumbs/caliper_pin2.jpg (http://www.saturnfans.com/photos/showphoto.php?photo=48717) This is the pin which appeared to be dry when I initially took the caliper off.
http://www.saturnfans.com/photos/data/500/thumbs/caliper_pin1.jpg (http://www.saturnfans.com/photos/showphoto.php?photo=48716) And here is the other bolt. Lubricated, but the bushing is possible bad? (Hard to tell in this picture)

After reading all the posts about people breaking pins, I think I'm going to wait until I have new parts in hand before I try to take the bolts out.

So am I crazy to think the pins/bolts and the bushing could be the problem?

1saxman
09-18-2008, 10:54 AM
This is why I take my brake work to the shop. I wish I could help you, but I have no idea why they squeak.

The Critic
09-20-2008, 01:02 AM
Hi tballard,

Welcome to SaturnFans.

I always replace the boots and pins if they look worn. I doubt that it's the cause of your noise, but it's important that these parts are in good condition so that the caliper can slide freely. I checked RockAuto and I see the caliper boots, they are sold by Raybestos, part #H5681A. They are listed under the "Disc Brake Hardware Kit" section.

As for the noise itself, it sounds like you've taken all of the steps that I usually take when troubleshooting these problems. I read that you took off the clips, but did you clean them (and the surface that they sit on) before reinstalling them? Sometimes this can be the cause of the problem. Also, GM actually recommends that their disc brake pads be installed dry without any lubricants or anti-squeal compounds. The AutoZone person is correct that the disc brake quiet compounds are for shimless pads only. Using those compounds on a shimmed pad can cause the shim to separate from the pad's backing plate over time.

I would also change the bed-in method that you've been following. Most of the instructions that you see online are tailored toward high performance brake pads. The "OE equivalent" replacement pads that you purchase cannot handle the temperatures resulting from following the bed-in methods that you see online. You might glaze the pads. Instead, perform 20 to 30 moderate stops from 30 mph. Wait at least 30 seconds between each one. This method is the one that GM, Bendix and Wagner recommends.

I think your problem is with the rotors and pads themselves. I have personally had poor success with the Duralast brake products. I had a set of their Duralast Gold pads on the rear discs of my SL2. I tried caliper grease, cleaning the hardware clips, pad bedding and rotor resurfacing, but none of these would resolve a squeak that I would hear as I came to a near stop. When they wore out, I replaced them with a set of NAPA Adaptive One pads and Centric Premium rotors. I have yet to hear the noise again.

Since AutoZone has a rather liberal return policy, I suggest returning the pads and rotors and starting over with something else. I would try the premium line of pads and rotors from a major brand. As I mentioned earlier, I have had good results with the NAPA Adaptive One pads and the Centric Premium rotors. I have also used the Raybestos Advanced Technology ceramic pads and the Raybestos Advanced Technology rotors on another car with good results as well. The Akebono ProACT pads have also worked well for me.

I priced out those Raybestos Advanced Technology pads and rotors for your car and they came out to about $165 shipped on RockAuto after a discount. That probably isn't much more than what you spent at AutoZone.

Good luck!