I have a 95 E320 w/110K miles that is in great running condition. In the last couple months I have been getting cabin noise that is getting louder and louder untilit's almost unbearable. At first it just sounded like road noise from the tires. I am running Michelen Energy MXV4 that have about 10K miles on them. I recently had them rotated (for the 2nd time) and all re-balanced. The noise was not affected by this at all. The noise is definately related to the rolling speed of the wheels. It is noticable even at speeds of 20mph, and gradually increases in intensity, maximizing at around 40-45 mph. It decreases at faster speeds, but is still noticable. When the noise is at it most, is is almost impossible to have a normal conversation. It is not engine noise, as I can shift into neutral during noisy times and rev and idle the engine with no effect. There is a very slight drift in the alignment (it is getting re-aligned tomorrow), and when I pull back against the drift or generally turn the wheel slightly to the left, the noise increases. The noise sounds like road noise, but the volume is incredible. It's like having a blender going on low all the time when driving at 40-45mph. I have had the car for 3 1/2 years and no problems. Has anyone heard of road noise in MBs like this? Could it be something related to the rolling speed that is not road noise? Thanks.

Have you checked your drive shaft bearing when it goes it causes a loud roar sounds like it comes from the middle to rear of the car. It could also be a bearing problem in your wheels. Did you have rotors replaced recently by chance?

The fact that the noise drops off at higher speeds is telling. (If it were "road noise" the intensity would continue to increase.)

So it seems logical to conclude that there's something funky with either the transmission or possibly the differential.

It would help if you could better pinpoint from where the noise emanates (I've found that opening the windows--reducing the echo chamber effect--and having a friend listen from different locations in and around the car sometimes faciltates this.)

Good luck in solving what I'm sure is a frustrating problem.

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Eric

1991 560SEL-Euro (214,000 miles)
1989 420SEL (Retired from daily use at 325,000 miles; Use as donor vehicle)

From the drivers location, the noise seems to come from the front wheels. The rotors were replaced about 15k miles ago. I have tried to listen for external noise by leaning my head out the window while driving at different speeds, and I never hear anything suspicious. Having the windows up definitely magnifies the noise with chamber echo.

I would check your bearings on the front wheels

Have a '90 Honda Accord my wife had been driving, which I took over. She complained of noise, and it was quite loud at certain speeds - similar to a bad bearing roar. I checked for bearing problems, and found none, but by rotating wheels front/rear the sound seemed to shift its location a bit.

Since I didn't like the handling anyway with the Michelin MXV on 14" narrow steel rims, I replaced with wider 15" alloy wheels, and Yokohama touring tires. The noise disappeared completely - and handling is much better.

Tire problems may not be apparent on inspection. With 40k+ miles, the MXV's still had plenty of tread, and wear looked even.

Steve

I drove a '98 e320 wagon that behaved similarly to what you described. It turned out to be due to a bent wheel... If you can do a swap for wheels/tires it would be one quick and decisive test. Perfect for a dealer if you don't mind the expense....

Good luck and kindly keep us posted!

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...Tracy

'00 ML320 "Casper"
'92 400E "Stella"

I am driving a C180 and it has an unknown Simes brand on it which has quite big threads, but does not make any noise at any speed. My previous car, a Camry was using Goodyear tyres which looked quite normal, but really made a big noise especially at highway speeds(100kmh) and also made the steering wheel vibrate very uncomfortably. Found out that they were ? defective as they were not really round in the sense that they had flat spots and were only 6months old. Changed to Bridgestones and the noise immediately disappeared together with the vibrations. There were some "techs" out there who were going to help me spend some of my little money to change shock absorbers, springs, engine mounts, mufflers, bearings and brake discs!Yokohamas are really "soft" tyres and should give a quiet roll at all speeds. Some tyres get flat spots when left for too long in parking mode. Good luck.

When listening for noise with the windows down, it is very helpful if you can find a street with very high curbs, or better yet, a sound wall. Whatever noise your car is making, it bounces off the curb or sound wall and you can hear it clearer. In narrowing down the problem, try:

different road surfaces - if the sounds goes away or is altered, then it points to the tires.
change gears (from 4th to 3rd) when driving at 45 mph - if it changes, then it's related to the engine or transmission.
put the car into neutral and rev the engine - if you hear it, then engine related.
check you tires for odd tread wear, exposed belts, etc.
while in the garage, open the hood and rev the engine and see if you hear something that sounds like the sound you hear on the road.
if the noise is consistent and can reproduced on command, then take a mbz tech for a ride and ask them what they think.

Before going to dealer, try to rule out the tires. Dealers always like to blame things on the tires.

Driveshaft center support and bearing!

I started this thread with my road noise complaint. I've been using the same independent MB shop for the last few years. I have always been impressed by their work. The shop is spotless. The owner spent 30 minutes walking me through the entire place after they closed up one night when I firsst started taking my car there. He pretty proud of the place.

Anyways...I took my mistress in for a lube/oil/filter today and also talked about the road noise with him. (I have been gone for a week but my wife was driving the car while I was away, and I noticed the noise had diminshed a fair bit in the last week.) I suggested he check the wheel bearings. He said they would put it on the rack and take a close look. He returned about 30 minutes later after the oil change and said the wheel bearings looked pretty bad and really needed immediate attention.

He had all my maintenence records in hand while talking with me and pointed out that they had repacked the front wheel bearings about 16 months ago when the brake rotors were replaced, and they should not have deteriorated in such a short time. He didn't know if materials failed or they missed something before, or didn't repack them right. (These guys do top quality work.) He offered to do the work at reduced cost and said it would be about 5 hours before I could get the car back. This was a problem because I had to pick up my kids in that time frame, so he offered me the free use of his personal MB until mine was done.

On picking up the car he said there would be no charge for any labor. He installed a full wheel bearing kit on both front wheels. I paid for the parts. We talked a bunch about things, and I never felt for a second they were to blame for anything. He was concerned about having a happy client. I've spent about $1500-$2000 with him in the last few years. It cost him about $150 in labor, but it will keep me coming there.

The car rides like a dream (again) and is as quite as a mouse.