Growling/Grinding/Chuffing/Clicking Sounds From Front End

F-Body brakes do fit under stock wheels!

Yes, hub-centric rings are installed. There is no vibration at speed. For that matter, there is no noise at speed, either. It's only when I slow down below 25 mph that it becomes audible.

There is a faint howling sound above 65 mph, but I'm beginning to think it's unrelated. Another clue: after sustained high speed trips, none of the wheels feels warmer than the others. Often a bad bearing can be revealed by touching each hub.

I am wondering if you have a heat shield or backing plate loose. Check over the cat, behind the wheels both sides; also check the air dam panel under the radiator support and the plastic inner fenders both sides. Check for a broken or loose brace under the front bumper skin (they are near the turn signal/side markers). Check for debris/animal nest in the chambers where the horns are (under the inner fenders, front, both sides.

While you are at it check if the sway bar end links are actually attached. If you have the OE links, when they break it might not be obvious.

Just ideas. Won't take long to look, point is eliminate the easy stuff before we do anymore teardown.

Because your transmission is next...

Albertj

I've looked over most things simply by working on the car periodically. The suspension parts are fresh, everything is clean in there. Most every part has been replaced at some point - newer brakes, fresh pads, new brake lines, tie rod ends, control arms, fresh motor mounts and cradle bushings, new struts & strut mounts. Hub/bearings are not brand new, but installed within a few years ago. Only thing not new is the axle, which turned out to be in fine condition.

I think I'd know if the Addco sway bar, and custom urethane links installed last year (the kind that don't go bad) were not in 100% shape. Taking a 95+ mph turn and not flying off into the tire wall kinda reassures that all is good.

So the easy stuff has already been eliminated - just by having the wheels off periodically, being under the car creeping around, replacing things, actually greasing the chassis parts every 10-15k miles as the owner's manual recommends. There's nothing unsecured, loose or dragging, or unaccounted for. For example, ALL the plastic fasteners that hold the fender well together have been replaced with new this year. That's how well the car has been maintained.

So far, I'm leaning toward it being a bearing or wheel stud issue.

Quote :

Because your transmission is next...

Ha-ha, why do you think this? The noise doesn't appear to come from that area. Also my transmission was rebuilt 85k miles ago. Trans fluid change 2k miles ago showed no indicators. Do you think the sound in the video could be transmission-related?

That's very specifically a rotational noise. So it has to be in the bearing, or lug nuts/studs/wheel.

Maybe you stress cracked one of the wheel spokes in your track outing!

Ouch, I hope that's not it. Come to think of it, it's time for a front to rear tire rotation.

AA wrote:

I've looked over most things simply by working on the car periodically. The suspension parts are fresh, everything is clean in there. Most every part has been replaced at some point - newer brakes, fresh pads, new brake lines, tie rod ends, control arms, fresh motor mounts and cradle bushings, new struts & strut mounts. Hub/bearings are not brand new, but installed within a few years ago. Only thing not new is the axle, which turned out to be in fine condition.

I think I'd know if the Addco sway bar, and custom urethane links installed last year (the kind that don't go bad) were not in 100% shape. Taking a 95+ mph turn and not flying off into the tire wall kinda reassures that all is good.

So the easy stuff has already been eliminated - just by having the wheels off periodically, being under the car creeping around, replacing things, actually greasing the chassis parts every 10-15k miles as the owner's manual recommends. There's nothing unsecured, loose or dragging, or unaccounted for. For example, ALL the plastic fasteners that hold the fender well together have been replaced with new this year. That's how well the car has been maintained.

So far, I'm leaning toward it being a bearing or wheel stud issue.

Quote :

Because your transmission is next...

Ha-ha, why do you think this? The noise doesn't appear to come from that area. Also my transmission was rebuilt 85k miles ago. Trans fluid change 2k miles ago showed no indicators. Do you think the sound in the video could be transmission-related?

Good point.

I went back and listened to the video. You get the noise when the brand ENKEI on the wheel is at 6 oclock and 12 oclock.

You might/should check that wheel for damage.

You also might/should check for debris trapped by the backing plate.

Good observation, albertj. The noise is two instances per revolution. Interesting.

Looked at the wheel from the exterior side, can't see any cracks or other indication of damage. Lug nuts are nice and tight. Need to rotate wheels soon.

Considering the noise is 2 per revolution, I am moving back to thinking this is either a wheel bearing or axle. Being that the axle has already been replaced, the bearing seems most likely. Maybe I will swap hubs left to right if there's time.

Wheel bearing makes sense. It's an unusual sound for that but autocrossing in a riv creates unusual stresses lol.

turtleman wrote:

Wheel bearing makes sense. It's an unusual sound for that but autocrossing in a riv creates unusual stresses lol.

Ummmmmmmmmmm, No.

The wheel deforms a little as it turns, which is normal. If you jack that wheel up off the ground and tap it with a plastic mallet (or something else hard that won't scratch it) you'll likely hear a tone about the same as the clink/creak you get when rolling and the ENKEI is at 6:00 or 12:00. You get the clink because when the wheel deforms the split moves at the crack. Crack probably hidden.

Give you a hint - put your donut spare on that wheel and run the test again. I think your creak will go away.

Given the circumstances I suspect the fracture is radial to the hub, not thru the hub. I suspect another hard track day or 2 and that wheel fails catastrophically.

Or it's actually your transmission.

Please for your own sake take 1/2 hour and put the donut on there and see if the noise goes away.

Albertj

I'm removing, inspecting, and possibly rotating the wheels tonight. That should tell us if the wheel is fractured.

In defense of the hub/bearing theory, the fact that one of the wheel spokes happens to be at 6 and 12 when the sound occurs doesn't mean it must be the wheel, it only means the noise happens twice per revolution. The alignment with a spoke could be coincidental. Still I won't yet rule out a cracked rim, although there doesn't appear to be anything wrong with it.

Another interesting pieces of info: Last night the noise was louder, but seemed to subside when turning right. On a hard right turn exit ramp, it seemed the opposite - the noise was louder when less load was on the right wheel. This morning the noise went away until I got to work. At lunch it was back.

It's got to be either the rim or bearing, and still a chance of a weak lug.

The plan:

1) identify if the noise moves with the wheel
2) replace lugs on the hub
3) replace hub

Bad hub. Last one was a Timkin, lasted on the car ~130k miles. That's 15k more than the OEM original. New Timkin goes on tonight.

AA wrote:

Bad hub. Last one was a Timkin, lasted on the car ~130k miles. That's 15k more than the OEM original. New Timkin goes on tonight.

Lesson learned, and thanks for posting followup

Albertj

It's funny that this post was bumped up because I think my driver side front hub is taking a dump as well. The car has always made a funny harmonic sound beyond 60mph but recently it has gotten a lot louder. It gets worse with speed and it loudest when I'm turning right. This seems to suggest that side is shot and louder when more load is on it. Going to replace it with a low mileage Morad special this weekend. lol

Sounds like yours is a textbook example of a failing hub. Mine was different. None of the typical symptoms you'd expect. Even now, the bearing is off the car, it turns perfectly smooth and doesn't feel loose.

Check our hub/bearing write-up if you need any help with the installation. I did mine in about an hour.

If not front hub, it could be your front strut upper mating kit. They have a bearing type setup atop the coil spring that get dirty or wore and makes a heck of a binding and grinding noise. With the right tools you can swap them out with new strut mount kits from Monroe in about 1.5 hours per side. Just did a set in a 2000 Lesabre custom the other day. Also inspect the spring itselfthere could be a break.

I put a replacement hub on the driver side of my car yesterday. The old one was definitely shot. It hummed considerably with load on it. When we took it out, the damn thing fell apart into three pieces.

The one I replaced it with was a low mileage used from Morad. I've always had good luck with his parts but I don't think this one is alright. I took the car on the highway this morning and the vibration now is WAY more than before. There is no humming sound when turning the wheel away from that side but the shaking is bad. This a sign of the bearing being crud? Or was my suspension happier with the crappy worn old bearing so that the worn components around the new one making for more vibration now? It probably sounds stupid... just curious what you guys think.

It could either be 1) the new bearing is also past its prime or
2) the the bearing on the other side is worn also and now with a good bearing one one side the other is now causing a vibration.
had that happen on a car in the past myself.

I think you can lift the front end and grasp the tire on both sides and if you hear a clunk its the hub.If you grasp the tire one hand on the top your other hand on the bottom and torque it,its the tie rod.

Did you have any trouble removing the old one? Possible you damaged something else during the process?

We didn't have much trouble getting the old one off so I don't think we damaged anything.

Driving more I've noticed that the vibration has lessened a lot. Not sure why that happened. Car seems better overall with the new hub on. The vibration seems to come and go. It's odd. I still need to check on the wheel balance as I'm sure that's not perfect.

Oh, I replaced the hub on the other side late in the summer and that's what caused the driver side one to crap out. lol

Can you pinpoint which wheel it's coming from? My guess is, the bad bearing covered up the slight vibration of an out-of-balance wheel. Now you can feel it. Has it been a while since you got the tires mounted?

Tires were mounted a month ago and from the get-go you could feel a little vibration. I'm just happy that whatever extra vibration I felt yesterday seems to have resolved itself. Maybe that was just the stretch of road I was on. I know some areas seem worse when you have a balance/suspension issue.

Got the tires road-force balanced earlier today. My local shop had the machine and did it for a very reasonable price. Will let everyone know how this pans out tomorrow. Haven't been able to drive the car yet. *fingers and everything else crossed*

Just wanted to keep you guys updated.

Took the car on the highway and the vibration is noticeably less. I'd say it is almost perfect now. There is still a tiny bit and it only seems to come in when the wheel is turned right. Whatever the worn part is, it makes for a humming sound when turning. I guess the hub Ed sent me might have been bad. It sounds the same as when the old hub was there. Is there anything else that would make that sound? Worn strut mount? Worn rack? I'm going to get the car in the air and see if there is play on the wheel at 3/9 o'clock positions.

It's not a huge deal at this point but will be addressed in the months to come.

Thanks again for your help guys.

Generally, yes the humming is a bad bearing (hub) if it's coming from one side during a hard corner. Don't know if you have the time, but I once needed to diagnose a bad bearing for sure, so swapped the left and right front hubs and listened for the noise to change location. If the noise moves to the right side, and gets louder when turning left, you've got a bad bearing. If you determine Ed's part is bad, he will give you a credit toward future purchases, but usually you won't get your money back.

To check the hub, rock the wheel 12/6 o'clock. 9/3 is better for showing worn tie rod/ends.