SL/R231: Wheel/tire hum
06-20-2023, 05:03 PM
#1
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Wheel/tire hum
This is driving me nuts so I'm going to throw this to the group.
I have a high amplitude hum when steering right around a bend in the road. It can be felt in the steering wheel, and body and can also be heard. It is of course speed sensitive and load sensitive being louder as load and/or speed increases. Straight ahead and steering left the hum goes away. Its the same sound and feel when a wheel bearing is starting to go bad.
So, I changed the drives side bearing and the hum didn't go away or change amplitude. Ok so then it has to be the tire or rim. Wrong, the hum is still there after I swapped wheel and tires around.
There is zero difference in the sound/feel with the brakes on or off so that rules out the rotor.
Have I missed anything? What do I check next?
I have a high amplitude hum when steering right around a bend in the road. It can be felt in the steering wheel, and body and can also be heard. It is of course speed sensitive and load sensitive being louder as load and/or speed increases. Straight ahead and steering left the hum goes away. Its the same sound and feel when a wheel bearing is starting to go bad.
So, I changed the drives side bearing and the hum didn't go away or change amplitude. Ok so then it has to be the tire or rim. Wrong, the hum is still there after I swapped wheel and tires around.
There is zero difference in the sound/feel with the brakes on or off so that rules out the rotor.
Have I missed anything? What do I check next?
06-20-2023, 06:04 PM
#2
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2020 GLC300 -2013 Sl550 - 1997 SL600
Internet drivability diagnosis is always tough but,
I always do bearings in pairs. the other wheel may not be loaded as much, but it still gets a side load.
Plus it’s just good general repair practice. But I get it, it’s a pain…
Did you do a visual inspection and physical test on the wheels/suspension. I.e. anything feel loose?
Mileage? How old are the tires? Remember the steering is electronic assist on these, any noise? (even slight)
Good Luck
I always do bearings in pairs. the other wheel may not be loaded as much, but it still gets a side load.
Plus it’s just good general repair practice. But I get it, it’s a pain…
Did you do a visual inspection and physical test on the wheels/suspension. I.e. anything feel loose?
Mileage? How old are the tires? Remember the steering is electronic assist on these, any noise? (even slight)
Good Luck
Last edited by crconsulting; 06-20-2023 at 07:06 PM.
06-21-2023, 10:17 AM
#3
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2020 S560 Sedan, 2019 SL450, 2019 E450 Luxury Trim Wagon, '24 BMW I7 on order...
My bet is on the tires being the culprit.
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crconsulting (06-21-2023)
06-23-2023, 03:04 PM
#4
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Thread Starter
Internet drivability diagnosis is always tough but,
I always do bearings in pairs. the other wheel may not be loaded as much, but it still gets a side load.
Plus it’s just good general repair practice. But I get it, it’s a pain…
Did you do a visual inspection and physical test on the wheels/suspension. I.e. anything feel loose?
Mileage? How old are the tires? Remember the steering is electronic assist on these, any noise? (even slight)
Good Luck
I always do bearings in pairs. the other wheel may not be loaded as much, but it still gets a side load.
Plus it’s just good general repair practice. But I get it, it’s a pain…
Did you do a visual inspection and physical test on the wheels/suspension. I.e. anything feel loose?
Mileage? How old are the tires? Remember the steering is electronic assist on these, any noise? (even slight)
Good Luck
To your questions: I had both wheels of and the liners off during the winter to check for loose parts and found nothing. The car also tracks perfectly and there is zero vibration when driving straight ahead or turning left. The car has 130,000 km on it but was really well maintained by the original owner. Tires on both front wheels are 10/21 so not that old at all and have about 35% wear. There is no play or noise in the steering gear and the electric assist is dead quiet.
I've had dead wheel bearings on many cars and this what it feels like.
The noise is like a growl that increases with the rate of turn in and speed and is felt in the steering wheel. Best felt and heard on a right hand turn entry ramp at 80-100 kmh. The hum does not match tire rotation frequency.
I'm really beginning to think I bought a faulty wheel bearing.
06-23-2023, 03:06 PM
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06-24-2023, 11:11 AM
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2020 GLC300 -2013 Sl550 - 1997 SL600
Hey CR, thanks for your post. I got sidetracked (as usual) so didn't get back here until today.
To your questions: I had both wheels of and the liners off during the winter to check for loose parts and found nothing. The car also tracks perfectly and there is zero vibration when driving straight ahead or turning left. The car has 130,000 km on it but was really well maintained by the original owner. Tires on both front wheels are 10/21 so not that old at all and have about 35% wear. There is no play or noise in the steering gear and the electric assist is dead quiet.
I've had dead wheel bearings on many cars and this what it feels like.
The noise is like a growl that increases with the rate of turn in and speed and is felt in the steering wheel. Best felt and heard on a right hand turn entry ramp at 80-100 kmh. The hum does not match tire rotation frequency.
I'm really beginning to think I bought a faulty wheel bearing.
To your questions: I had both wheels of and the liners off during the winter to check for loose parts and found nothing. The car also tracks perfectly and there is zero vibration when driving straight ahead or turning left. The car has 130,000 km on it but was really well maintained by the original owner. Tires on both front wheels are 10/21 so not that old at all and have about 35% wear. There is no play or noise in the steering gear and the electric assist is dead quiet.
I've had dead wheel bearings on many cars and this what it feels like.
The noise is like a growl that increases with the rate of turn in and speed and is felt in the steering wheel. Best felt and heard on a right hand turn entry ramp at 80-100 kmh. The hum does not match tire rotation frequency.
I'm really beginning to think I bought a faulty wheel bearing.
How did the old bearing look? Rears OK?
Name brand tires? No weird (MEASURED and visual) tire wear? 80k miles isn’t too bad, but hard to know previous history unless you’re the original owner. Did it always make the sound or new development?
You’re looking in the right places….
keep us posted.
Good Luck
06-25-2023, 12:25 PM
#7
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Here's the old bearing. No play in it at all. When turned by hand, there are no rough spots. It actually feels like a new bearing.
Tires are Bridgestone Potenza. No visible damage and wear is even
Last edited by Montreal300; 06-25-2023 at 12:27 PM.
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06-25-2023, 01:33 PM
#8
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2020 GLC300 -2013 Sl550 - 1997 SL600
Probably not what you want to hear, but probably not (that) wheel bearing,
I once had a guy who brought me a car that had a hum when you turned the wheel like that, Turned out he had the wrong lug bolts! ☹️
Sometimes it’s something obvious, but so ordinary it’s easily overlooked.
Look at the inside of the wheels where the wheel bolts to the hub flange. It should be nice flat and clean machined surface. I’m assuming these are factory wheels right? Also inspect the center bore & machined mating surfaces of the wheels for any irregularities. Tires also typically high on the suspect list, but as you say they are relatively new 😕. Suspension too (tie rods and ball joints) in extreme cases, can show up as steering wheel vibrations too.
It’s there, unfortunately you need to keep searching. It will probably be obvious when you find it…..
Frustrating I know ☹️
Good Luck
I once had a guy who brought me a car that had a hum when you turned the wheel like that, Turned out he had the wrong lug bolts! ☹️
Sometimes it’s something obvious, but so ordinary it’s easily overlooked.
Look at the inside of the wheels where the wheel bolts to the hub flange. It should be nice flat and clean machined surface. I’m assuming these are factory wheels right? Also inspect the center bore & machined mating surfaces of the wheels for any irregularities. Tires also typically high on the suspect list, but as you say they are relatively new 😕. Suspension too (tie rods and ball joints) in extreme cases, can show up as steering wheel vibrations too.
It’s there, unfortunately you need to keep searching. It will probably be obvious when you find it…..
Frustrating I know ☹️
Good Luck
Last edited by crconsulting; 06-25-2023 at 01:42 PM.
06-25-2023, 01:41 PM
#9
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Thread Starter
I think you're getting why I'm so frustrated
New lug bolts all around. No change.
OE wheels swapped side to side with zero difference. Next on the list is the rear wheel bearings.
New lug bolts all around. No change.
OE wheels swapped side to side with zero difference. Next on the list is the rear wheel bearings.
