Help! Misdiagnosed.. Not a wheel bearing

202k mi, 2003 Golf TDI ALH
Stock, besides Koni SRT.T "Orange" dampers.

A bit ago I started hearing a noise from what seems like the right side of the car, getting worse and worse until now it's louder than the engine while on the highway...

It starts making noise above ~40mph, and is vehicle speed based (aka engine speed doesn't make a difference, transmission in any gear, also neutral doesn't change the noise). The noise (kind of a low grinding noise, almost sounds like a vibration but I'm not feeling anything) gets louder when you turn the car to the LEFT, and goes away when you turn the car to the RIGHT. It also has a braking noise/wobble under mid-hard braking from speed (also seeming to come from the front right)

There is A LOT of dust/ crud on the front right wheel, and not on any others, all of the brake pads and disks having been changed recently.

Now, I mis-read this as a front right wheel bearing, and tore the car apart and got the hub off to change the wheel bearing. Once that was changed (only forgot the retaining clip... once), I got the car back together (also changed the ball joint since I was in there). No change, same symptoms despite the new bearing and ball joint.

So.. I'm stuck, and frustrated. Did I just get it backwards, and need to do the left bearing instead? Is there something rubbing on the driveshaft or the wheel (I need to go looking)? Other things I may not have thought of?

Open to ideas, and learning. Thanks in advance!

-Ryan

http://forums.tdiclub.com/showpost.php?p=4394708&postcount=16

Using your ears can be midleading

It may be a wheel bearing, just not the right side. Failing wheel bearings make noise when unloaded, go quiet under load. So when you turn left the left side is unloaded, and the left wheel bearing will make noise. When you turn right the left wheel bearing will go quiet.

Check out the driver's side bearing.

snakeye said:

http://forums.tdiclub.com/showpost.php?p=4394708&postcount=16
Using your ears can be midleading

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Yep, why I said 'seems' in the post. :/ I found conflicting info on the which way the wheel turns to which one makes noise theory, and I should have listened to the advice I had gotten in the past instead of the internet...

Having spun all 4 wheels while holding the spring, I can say with confidence that the LEFT front has a vibration, and the rest do not (nothing at all really). I had read about this before I started but had not spun the wheels and touched the spring. Shame on me, but at least I learned something? Maybe? Hopefully?

My dad told me way back in the day that it was the UNLOADED wheel that makes noise (AKA the LEFT wheel would make noise when the car is turning LEFT and vice versa), but what I ended up reading was saying the opposite. This was the main driver behind the choice to do the right side.

Check the pads aren't extra worn on that wheel already but also could be the drive shaft. I've had motors come into the shop I used to work at, drive shaft bolts were all loose.

Couple of things of the bearings check out.

Seatman said:

Check the pads aren't extra worn on that wheel already but also could be the drive shaft. I've had motors come into the shop I used to work at, drive shaft bolts were all loose.

Couple of things of the bearings check out.

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Double-checked the pads while they were out, same thickness both sides, didn't throw a caliper on the disks though.

I replaced the caliper pins and rubber guides on both sides (because old, and cheap to replace), and plan on doing the lines as well but hadn't thrown those in. The lower driver-side pin threads are stripped in the knuckle (that could be my brake noise?), plan on putting a thread insert in sooner rather than later.

Not trying to promote our own stuff, but these are an easy fix: https://www.idparts.com/oversized-brake-caliper-slide-pin-a4-p-10230.html

You can buy them at Autozone, too.

As far as noises on wheel bearings go, I have found that the double roller bearing in the fronts on our cars make noise when they are unloaded. Typically though, a tapered roller bearing (used on countless front spindles on American RWD cars from the 60's up through the 90s) will make noise when it is loaded.

As you have found though, best to compare both sides to really nail down the source. I can see how the crud on the wheel can lead you on...

Noise that changed with curves is almost always a wheel bearing. If the noise get louder to the left and quieter to the right it is indicative that a right side bearing has failed.

Be aware though that there are two bearings, left and right, at each wheel. They are often incorporated into one outer shell but there is two separate inner bearings and races.

I have seen mechanics that I thought were quite good mistakenly replace the wrong side bearing due to assuming by sound on turning and ignoring that there are two bearings per wheel actually.

I listen, look, shake, run them in the air on the hoist and take my best guess which side. Before replacing blindly I also double check after the axle, rotor and brakes are removed, I give the hub a quick spin by hand. Usually you will hear the teltale noise then.

IndigoBlueWagon said:

Not trying to promote our own stuff, but these are an easy fix: https://www.idparts.com/oversized-brake-caliper-slide-pin-a4-p-10230.html

You can buy them at Autozone, too.

Click to expand...

Love you guys <3 most of my parts (and all of my oil change kits) come from you. We'll see what it sounds like when it's all back together. I'd rather put a helicoil in it and use a regular pin, but we'll see what happens.

Nutsnbolts said:

As far as noises on wheel bearings go, I have found that the double roller bearing in the fronts on our cars make noise when they are unloaded. Typically though, a tapered roller bearing (used on countless front spindles on American RWD cars from the 60's up through the 90s) will make noise when it is loaded.

As you have found though, best to compare both sides to really nail down the source. I can see how the crud on the wheel can lead you on...

Click to expand...

Yep, and good to know that they can fail with different sound profiles.

Thanks everyone for the quick and thorough responses. Always frustrating to mess it up, but at least now I know!

IndigoBlueWagon said:

It may be a wheel bearing, just not the right side. Failing wheel bearings make noise when unloaded, go quiet under load. So when you turn left the left side is unloaded, and the left wheel bearing will make noise. When you turn right the left wheel bearing will go quiet.

Check out the driver's side bearing.

Click to expand...

Opposite is more common, noise turning left is 99% of the time the right side bearing. It's usually the outer race that fails and you hear it under load or straight on but quiet when not under load.

My experience is the reverse. Maybe this is why people get this wrong so often. Perhaps their behavior isn't consistent. One thing I do know is I can't diagnose which rear bearing is bad by driving the car.

eldar11 said:

... The lower driver-side pin threads are stripped in the knuckle (that could be my brake noise?), plan on putting a thread insert in sooner rather than later.

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This ^^^.


I tried the repair pin, but it only worked for a few miles before something went awry. If it works for you, then great. If not, idparts also sells the complete knuckle.


I also tried a used knuckle, but it had the same problem. So I ended up buying a complete new Moog knuckle anyway, after all the troubles.


To me, having excess dust and noise from the one side points directly at the brakes, and having just barely been through the very problem you mention, then it HAS to be the pins. You can't have good brake performance if one of the pins is off. With this information, I don't know why anyone is talking about wheel bearings still. BTDT, got the freakin' t-shirt.



Good luck,


PH

IndigoBlueWagon said:

My experience is the reverse. Maybe this is why people get this wrong so often. Perhaps their behavior isn't consistent. One thing I do know is I can't diagnose which rear bearing is bad by driving the car.

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Rears area pita till they get really bad most of the time. It's satisfying when you spin the hub and it's noisy, you know you've got it nailed lol


But yeh, regarding the front it's usually the outer, I think I've seen it once being the opposite side but the inner race had seized at some point and knackered the actual hub! Ooft!

Powder Hound said:

I don't know why anyone is talking about wheel bearings still. BTDT, got the freakin' t-shirt.



Good luck,


PH

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Because it isn't confirmed that that is the problem yet, just something the OP has found. I've seen a number of those stupid threads stripped but none have been noisy in the way the OP describes. Maybe a rattle.

But yeh, I'm gonna wait till the final verdict is in lol

Powder Hound said:

This ^^^.


I tried the repair pin, but it only worked for a few miles before something went awry. If it works for you, then great. If not, idparts also sells the complete knuckle.


I also tried a used knuckle, but it had the same problem. So I ended up buying a complete new Moog knuckle anyway, after all the troubles.


To me, having excess dust and noise from the one side points directly at the brakes, and having just barely been through the very problem you mention, then it HAS to be the pins. You can't have good brake performance if one of the pins is off. With this information, I don't know why anyone is talking about wheel bearings still. BTDT, got the freakin' t-shirt.



Good luck,


PH

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The brake noise (wub wub wub at higher frequency) is separate from the assumed wheel bearing noise. Wheel bearing noise happens at all times when the car is moving above ~35 mph, unless I turn the car to the right. Brake noise happens only while braking from speed (50-60mph) and includes a bit of a shake through the steering wheel, they are two separate noises. That's not to say that they are not related though...

Using the wheel spin and hold the spring method, there is a VERY obvious grinding/vibration on the driver's side that is not present on the passenger side.

Something I just ran into on the '02 Golf I recently acquired, maybe it is something to look at...

I had a noise which sounded sort of like a dust shield contacting the rotor that got worse when turning in in one direction. I also had what felt like a warped rotor, with a decent amount of pulsation in the pedal.

Turns out it was not a warped rotor or heat shield contacting the rotor, but the ABS tone wheel itself. Somehow it got bent toward the strut over an inch or two badly enough that it was contacting the ABS sensor, and apparently also the inner brake pad. I have no idea how this happened; it was like that when I got the car. I carefully bent the tone wheel back in with a screwdriver and the noise and pedal pulsation were gone.

Something to look for, in any case.