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Squeak 20 miles after changing the pads and rotors, but I don't think they are the problem

Hi everyone,
I just bought my first car, a 2000 saab 9-3 convertible (base model) a month or so ago. The car had been neglected for the last year or so and I have been spending the last few weeks fixing all its issues. This last weekend I replaced the rear shocks, font struts and the rotors and brake pads on all four wheels. After driving about 20 miles or so I started to notice a squeak coming from the front right wheel well and since has become more and more noticeable/pronounced. Hopefully you all can help me figure out what I need to fix as I am a poor college student and cant afford to take it to a mechanic but also want to maintain the car so I can keep it for as long as possible. I also don’t want to to be driven insane from the constant squeaking.

Squeak description:
-cyclically increases and decreases in volume with each rotation of the wheel

-the squeak is constant: squeak that gets louder at a certain point in each wheel rotation but is always a certain baseline volume as long as the wheel is turning

-the volume of the squeak is NOT AT ALL effected by braking (EXACT same noise driving as while braking) which leads me to think its has nothing to do with the pads or rotors

-HERE IS THE WEIRD ONE: the squeak disappears completely when driving in reverse!

-the squeak is about the pitch and sound of a cricket, only constant and Ii guess louder.

-the noise is unaffected by turning sharply to the right and left.

Additional details:
-I had to use a gear puller to press the axle out of the wheel bearing (was stuck from rust). I hooked to the back of the wheel bearing ( what the lug nuts screw into ) and pressed on the center of the axle. Maybe this could have damaged it or the cv joint?
-while I was switching that wheel’s strut insert out, the carrier bearing leaked 1 (maybe 1 and a half) teaspoons of grey oil from the larger end of its boot and stretched out an inch or so from the weight of the hanging axle. (was really confused as to why that happened)

I think this is a better description than most, so I hope you all can help me. Thanks in advance for all your words of wisdom, your experience is very much appreciated!

-Brian

Try to isolate which wheel is causing the squeak and double check everything. Your description sounds like a piece of brake hardware (probably an anti-rattle clip) or backing plate that is too close to the rotor and intermittently making contact with it.

I’m in agreement with mark9207 that this could be caused by brake hardware and his advice about narowing down which wheel it is. On the offchance that it’s not you might consider the possibility of a squeaking wheel bearing.

You refer to neglect and rust so it’s possible the bearing, if not squeaking before, could have been prodded to do so by the force exerted by the puller.
It’s also possible that a wheel bearing can act strangely. (The disppearing in reverse.)
Generally speaking though, a wheel bearing noise will change tone during cornering.

My hat’s off to you for being so thorough in describing the problem. Many would have just stated that “my car is making a funny noise. What could it be?” :slight_smile:

My bad. I had forgotten the part about the right front. I’d remove that wheel and go over the brake components again.

The assembly that holds the wheel bearing is called the steering knuckle. The part of that assembly that rotates and the axle goes through is called the hub, the studs for the lug nuts are pressed into the hub. What you are calling a carrier bearing is what we call the wheel bearing.

If you had grey oil come out of the wheel bearing, I would say that it needs to be re-greased. That may not be doable if the wheel bearing is a sealed unit, you will need to replace it. But wheel bearings don’t usually squeak, they tend to make a growling sound.

When you are going down the road, your car oscillates up and down. If the squeak has a periodic variation that is not directly related to speed, then the squeak is probably coming from the spring. It is either not completely seated or it is missing that little plastic coating on the spring seat.

If this was your first strut replacement, I’d guess that the spring is not fully seated. It seems to be a common problem with strut replacement.

In response to keith:

I guess what I am calling the carrier bearing is the assembly that houses the tripod bearing, it is what leaked the oil I talked about. (the link here has a picture of the part i’m talking about hxxx://data.eeuroparts.com/Images/parts/md_61de69fd-db85-42b2-9b99-c5f54dc1d4a5.jpg replace the three x’s at the beginning of the link with ‘ttp’ as I’m not familiar with whether or not this forum allows links or not). The oil that leaked out of this part seamed to seep out of the interface between the large end of the boot covering the tripod bearing and the metal assembly housing the bearing that the boot is hose clamped to. (look at the pic if my description is not clear enough, hopefully it will clear up any of my possible mistakes in terminology) the hose clamp on it does not appear to be removable without cutting it off, does this mean I need to replace that whole assembly? or should I just open it up and smear in the appropriate grease and install a screw driven hose clamp as a replacement?

The thing I gripped with the gear puller I guess is called the wheel hub, and the bearing in there did not leak the mentioned gray oil, but I was worried that i could have damaged the bearing in there as the axle had rusted to its inner race. (which is why i used the gear puller)

as for the spring not being seated, I suppose its possible, but I doubt that is the issue as the squeak cycle is directly proportional to speed as you said, I should have mentioned that more explicitly in my first post. I also was very careful to make sure the spring was seated when I installed it, unless a mill makes a difference I would say I am sure that the spring is seated properly. It also has that little plastic coating (cleaned and) installed.

ok4450:

I too immediately thought that it was the brakes, so I did the full break in procedure, but that didn’t help. So I took the wheel off and looked at the caliper, and it looked ok… I mean this particular caliper only has one spring (retaining spring) which was where it should be, aside from the spring the only other easily remove-able parts on the caliper are the pads and those look well seated. ITS SO STRANGE!!

Mark9207:

Read what I wrote to ok4450 above, it has to do with your suggestion. Also the pads I installed do have backing plates, but they are glued to the thicker steel back plate of the pads. (don’t know if this matters, but I also slathered the backs with anti-squeal and let it dry before I installed them)

Thanks everyone for your Ideas, please keep them coming. Hopefully my replies to each of you help to make the the problem clearer to you all. I want to provide as much info as I can so you have the whole picture. If you think of any tests that I can do to help diagnose the issue please let me know. I am thinking of putting the car up on jack stands this weekend and having someone give the car some gas while I listen for the source of the squeak. I’m thinking if it goes away on the stands then it cant be the brakes as they should not be effected by loading the wheel. It would then have to be the wheel bearing or that tripod bearing thing then wouldn’t it?

Thanks again in advance for all your help.

The “noise goes away in reverse” makes me think this IS brake-related.

When pads touch the rotor trailing-edge first, they tend to squeak a lot less than when they touch leading-edge first. So, if the pads are ever-so-slightly “mis-shimmed,” they’ll squeak going forward (leading edge makes contact first) than going in reverse (trailing edge first).

Make sure all the anti-rattle equipment is installed and in good condition. Try using anti-squeal compound. Try using some anti-squeal compound.

Does this car have a dust cover on the brake? It could be bent or cracked/

Do your new pads have beveled edges? If not, you might try putting a beveled edge on the leading and trailing edges of the pads. This usually helps eliminate a lot of squeaks, and is cheap and easy to do. A bench grinder works well for this. Be sure to wear a dust mask or respirator when you do this as a lot of dust will be made.

Is the tripod bearing on the axle? Are you talking about the CV Joint?

I want to start off by saying thanks again for all your help you guys!

I did notice today that now the squeak seams to decrease noticeably in volume when I quickly change lanes while going 30+ mph turning to the right. (this would shift more of the cars weight to the left side wheels and off of the squeaking front right wheel) -> I guess this would indicate that the volume of the squeak is proportional to wheel load. (In my first post when I said the squeak was independent of what direction I was turning I had tested this by turning and driving in circles in a parking lot, so maybe I wasn’t moving fast enough, or was turning too sharply to notice this) Does this effect any of your guesses as to what the problem might be?

Meanjoe75fan:

That’s an interesting point you bring up. I had thought about what you said about the leading edge and squeak being louder when I noticed this symptom. I worked in a bike shop for a year or two and that same sort of thing sometimes happened when I was working on those disk brake setups. I wasn’t sure if it would transfer to car brakes and rotors though… from what you say I guess it does. I will definitely check that when I try and work on the car tomorrow. From the outside the caliper and springs all appear to be where they should be ( same as before I changed the rotors and pads), but I suppose the issue could be with the inside pad/ piston side. Maybe the rubber seal is dead and isn’t allowing the pad to retract from the disk… good idea.

OldTimer 11:

Wow! actually thinking about it now I think I remember that one looked a bit bent when I took It off. I remember trying my best to straighten it, but maybe I didn’t do it perfectly. Will definitely check this this weekend. The only thing is I think it’s bit odd that the squeak didn’t surface until about twenty miles after I did the work. If it was a bent dust shield, I would have expected it to make noise from the get go. Either way I am definitely going to give that a thorough inspection tomorrow.

Mark9207:

Good idea about the beveled edges on the pads. The pads I got are Akebono Euro Ceramics and come with a nicely beveled edge on them ( I got them because they were supposed to be very quiet… haha! would be funny if they turn out to be the issue ). Again, great idea though.

Keith:

I just tested the picture link (subbing in the ‘ttp’ at the beginning like I mentioned and the picture I linked should work. When I day tripod bearing I am talking about the bearing and boot on the right side of the image and when I say CV joint I am referring to the flexible metal bulge thing right before the splines for the hub ( on the right side of the pictured axle assembly). here is the link again without the weird address modification I did before. ( I will just hope this isn’t against the forums rules )
http://data.eeuroparts.com/Images/parts/md_61de69fd-db85-42b2-9b99-c5f54dc1d4a5.jpg

Great Ideas, keep them coming. I will let all of you know what I figure out about the issue tomorrow. I will try checking the brake set up again, and if that does not work I will re-install my old rotor and pads on that wheel and see if that fixes it. If it does, then I guess I have found the problem… if it doesn’t, then at least I have ruled the brakes out.