I have a 93 Toyota Corolla DX, Auto transmission, 202,000 miles.
There appears to be a humming noise coming from the front end. It sounds like a low frequency helicopter blade spinning about - like a 'whomp whomp whomp" sound. If you listen closely, it occurs at all speeds. It seems to be directly related to the sound of normal braking, and you can feel it ever so slightly in the steering wheel.
The frequency of the sound increases with road speed, and becomes most pronounced at 40 - 45 mph...
What I've done to trouble shoot:
1) A slide pin on the driver's side brake caliper was frozen. Caused brake pad rubbing - replaced pin and relubed the pins. Thought for sure that was it - however it wasn't.
2) Replaced driver side wheel bearing - as that wheel didn't spin very well. Didn't change the noise (but wheel turns well.) Passenger side bearing appears to be fine.
3) Rotated tires. No change.
I'm running out of ideas. The CV joins all look ok - no breakage and no clicking during turns.
I've only recently obtained this car so I don't know its history - I don't know if the sound is normal road noise, is typical of the tire (Michelin) manufacturer, or perhaps a binding caliper...
Any suggestions are greatly appreciated!
Call into Ray O....
You want someone that knows what he is doing....not NPR!
What?! Not a "Car Talk" fan?!? Somehow I cna't quite see you listening to or enjoyuing "Wait, Wait, Don't Tell Me!" (which I, OTOH, love!), but "Car Talk"???
On Sun, 24 Sep 2006 22:23:23 -0400, Cathy F. wrote:
I like WWDTM, but haven't listened to it for a while.
Same with Car Talk. I met Tommy and Ray some time ago when I used to live out near Boston. They are hilarious.
And their office has a window with gold leaf lettering that says, "Dewey, Cheetham and Howe".
wrote in message
(Whoa - didn't proofread or spell-check that one!)
I try to catch it every week. Love the sense of humor.
That's cool! It'd be pretty disappointing to find them *not* to be humorous IRL.
I know of someone who lives in Boston, whose plumbers are the Trethewey Bros. (re: Rich Trethewey of "This Old House").
Somehow this doesn't surprise me. ;-) The ironic bit being that I can't imagine those guys actually cheating anyone... Somewhere I think I read that only one of them is actually at the garage? (Maybe the other one - whoever's the elder - is retired, except for doing Car Talk?)
I wonder, if I ever called in, if they could correctly ID me as a Cathy with a "C"? <g> I'm pretty sure they could diagnose the car problem, as long as my explanation was clear & complete enough - with the correct accompanying noise if applicable! OTOH, owning Toyotas - which are 8 years or younger, hopefully I'd never feel a real need to call in.
I listened to that show when my boss was a guest on the show. A few minutes listening to these guys did not impress me with their automotive technical knowledge. They are OK with the stuff that one would learn in high school automotive shop class, but my boss and I were not impressed with their knowledge beyond that.
You mean like when they told the guy, with the RWD Ford van, that the noise in the front end was likely a bad CV joint? ;)
"Ray O" <rokigawaATtristarassociatesDOTcom> wrote in message
Thanks for the vote of confidence!
On Sun, 24 Sep 2006 20:11:48 -0400, Cathy F. wrote:
Gee, Cath, when was the last time they gave an ACTUAL answer?!
I used to listen to them when they first started in Boston, and it was a GREAT show for backyard mechanics. It was live, real time, and you could call and talk to them and get advice, and not have to leave a message and hoped they thought your call had enough 'entertainment' value to give you a call back!
My father-in-law just gave my wife the exact same car with 100,000 fewer miles on it and the exact same problem. In his case the sound started after some minor front-end damage (minor enough that if we painted the replacement hood to match the rest of the car, you would not be able to tell it had happened). I've eliminated the brakes and the wheel bearings and am, at this point, scratching my head much the same way you are :) I also checked to see if the wheel well liner was maybe cracked and dangling onto the wheel - no dice there.
However it did NOT make this noise previously, so it is definitely NOT normal road noise. Not sure what brand of tires are on it but they are the old-fashioned zigzag tread pattern, not these newfangled treads that look like bird footprints.
On Sun, 24 Sep 2006 19:55:20 -0400, SlyckTom wrote:
What I have experienced with this:
1. Shock has gone totally out of oil or gas 2. Tire has a broken belt. This really manifests itself at slower speeds with a modulation of the steering wheel, that goes away as you speed up. THIS IS EXTREMELY HAZARDOUS!!! Get this checked! 3. One of your brake calipers has sticking slides, and is heating up the rotor. This starts out normal, and gets worse the longer you drive. This is also hazardous.
You can check for sticking brakes by feeling the wheels after driving. If one wheel is hot and the others relatively cool, that's the problem.
The cause of noises is very difficult to diagnose without hearing the noise.
"Rotational" noises can come from several causes: Sticking caliper slide (I don't think you freed the slide properly); wheel bearings; tire problem like a broken belt; brake backing plate touching the rotor; CV joints; differential bearings; and engine noises.
The caliper bolt (pin) passes through a sleeve in the caliper body. If you look at the sleeve, there are rubber boots on the inboard and outboard sides of the caliper between the sleeve and the cast caliper body. You should be able to push the sleeves in and out of the caliper body, stretching the boots. The bolt should slide in and out of the sleeves, and the sleeves should slide in and out of the caliper body. If the sleeves are frozen, carefully peel back the boots, remove the sleeves (1 sleeve for each bolt/pin), clean up the OD of the sleeves, and lube with either caliper grease, wheel bearing grease, or anti-seize.
While you're at it, make sure there are 2 flat metal shims between the back of the pads and the caliper piston, make sure the anti-rattle clips and/or springs are place, and make sure the square keys at the ends of the pads are not loose in the keyway in the caliper bracket. Aftermarket pads sometimes fit loosely can cause noise, which is why I always recommend OEM pads.
The slide was freed properly. It had frozen in the bore, and I extracted it with considerable effort. One it was out, I threw it in the trash and purchased a replacement slide and bolt. I also replaced the dust boots, cleaned out the slide holes,and greased them with wheel bearing grease. They now slide properly as you describe and no longer drag on the disc.
All the tires are fairly new, and I've inspected them for belt breakage - none is apparent. I also feel the problem would have been isolated rom rotating the tires.
Granted I have replaced the pads with no-OEM pads (hence no anti-rattle clips, etc) the rotational noise existed before I replaced them...so unfortunately that is not the problem.
That leaves us with:
wheel bearings, CV joints; differential bearings; and engine noises.
I can eliminate the engine since it does it whether the engine is running or not. This also probably eliminates the differential since that is just a wildly unlikely senario in these vehicles.
So what I'm left with is either:
A binding caliper (worth looking into, but unlikely) CV joints (very possible, but there's no clicking during turns and the boots are in good shape), and finally, the passenger side wheel bearing.
I've done some research into the wheel bearing possibility, and that seems to be the most likely of senarios. But even this I am hesitant about since the wheel turns fine when its jacked up, and there's no free play. But from what I've read, this doesnt guarentee a bearing is in good condition.
Anyway, my next move is to replace the bearing and we'll see from there.
On Sun, 24 Sep 2006 22:01:43 -0500, "Ray O" <rokigawaATtristarassociatesDOTcom> wrote:
Yes, this is the proper method! (From your original description, I thought you just replaced the bolts.)
Your logic in analyzing the source of the noise is very good. I have seen wheel bearings make noise even though there is no free play. Good luck!
Thank you again Ray. And as a follow-up, I found an empty parking lot today, and turned the steering wheel all the way left, and spun 360 degrees a few times - very little noise other than the pavement.
I then turned the steering wheel all the way right and spun 360 degrees a few times again - and heard and felt a noise very similar to the rotational noise as described.
It's now becoming clear(er) that the driver's side bearings are to blame, since spinning left (the ones I replaced) yielded no appreciable noise.
So this weekend I'll replace them, and give an update...unless impetuousness gets the better of me ;)
On Mon, 25 Sep 2006 13:43:13 -0500, "Ray O" <rokigawaATtristarassociatesDOTcom> wrote: