HELP!! Buzzing Humming Sound from 2005 C230
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05 C230, 15 C300
HELP!! Buzzing Humming Sound from 2005 C230
I have a 2005 C230 with over 270,000 miles. The engine runs great except for the occasional P0420 code. However I have a buzzing/humming sound coming from somewhere whenever I get up to around 35 mph.
I thought is was the front wheel bearings because whenever turn left on the highway to go around a left hand curve, the sound goes away. The sound is always there when I go straight or turn right. But I changed both the front wheel bearings and the sound is still there. Then I thought it was possibly because the front tires were worn on the inside so I changed the tires, the control arms, the tie rods and got a wheel alignment and the sound is still there.
I'm convinced now that the sound is coming from the rear. One of my many questions is, would the sound from a bad REAR wheel bearing go away when I change direction? And is a rear wheel bearing a DIY job? I also read somewhere that someone was getting a buzzing sound from the rear differential.
Any help or hint would be appreciated.
I thought is was the front wheel bearings because whenever turn left on the highway to go around a left hand curve, the sound goes away. The sound is always there when I go straight or turn right. But I changed both the front wheel bearings and the sound is still there. Then I thought it was possibly because the front tires were worn on the inside so I changed the tires, the control arms, the tie rods and got a wheel alignment and the sound is still there.
I'm convinced now that the sound is coming from the rear. One of my many questions is, would the sound from a bad REAR wheel bearing go away when I change direction? And is a rear wheel bearing a DIY job? I also read somewhere that someone was getting a buzzing sound from the rear differential.
Any help or hint would be appreciated.
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2007 Mercedes E550
The sound could literally be anything. The only way to diagnose is to get under the car. It could be something really obvious like a loose heat shield. If you take it to a mechanic and just say you hear a noise might as well give him a blank check
Thread Starter
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05 C230, 15 C300
Rear wheel bearing
Does anyone know if the noise from a bad REAR wheel bearing would change if the car swerves or turns? The from my car completely goes away if I swerve or turn the car to the left.
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Thread Starter
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05 C230, 15 C300
There is no play in the wheel. It feels ok when I rotate it. I got the rear end on jack stands so that the rear wheels are off the ground, I put the car in Dyno mode and then put the car in drive. I didn't hear the humming sound with the rear wheels off the ground. I heard an intermittent scraping or scratching sound but it seem to be coming from both sides. I'm assuming that is just the rotors.
Also I'm assuming that I didn't hear anything because there was no pressure on the bearings. I don't know.
Also I'm assuming that I didn't hear anything because there was no pressure on the bearings. I don't know.
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Thread Starter
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05 C230, 15 C300
Fixed
You were correct. It was the left rear wheel bearing. I took off the knuckle with the hub attached and when I spun the hub, it sounded horrible. I bought a used knuckle, with the hub attached, from a salvage yard and now my car is back to being quiet. I had to change the bushing on the used knuckle but that was surprisingly easy with the Sir Tools M0085 tool. Thank you for your help.
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From: Carolinas
2005 C230K SS
You were correct. It was the left rear wheel bearing. I took off the knuckle with the hub attached and when I spun the hub, it sounded horrible. I bought a used knuckle, with the hub attached, from a salvage yard and now my car is back to being quiet. I had to change the bushing on the used knuckle but that was surprisingly easy with the Sir Tools M0085 tool. Thank you for your help.
Plus, if one bearing went out, the other side is close behind.
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05 C230, 15 C300
I got the used knuckle for $40 and I felt lazy. lol But I will replace the bearing in the knuckle that I took off the car. I just wanted a quick fix because I wasn't sure that was the only thing causing that racket. But you are definitely correct replacing it with a brand new bearing would have been the best option.
Last edited by C230WAK; Aug 9, 2016 at 04:37 PM.
