I'll admit up front that I suck at searching in forums....

My 2017 E400 4Matic wagon has developed a speed based vibration at 71K miles. Can't really feel it below 50mph. At 70mph, it's pretty noticeable and annoying. I'll take it to my new-found independent Mercedes mechanic after the holiday but hoping to learn a little bit before I do.

I just had a 4-wheel alignment and had all of the tires balanced. I also just did a transmission flush and filter/pan replacement.

The vibration is definitely not rpm related...at 70mph in 9th gear, it's the same as in 7th gear at 70mph.

I'm having a hard time finding a decent schematic of the 4MATIC system. Is there a hanger bearing on either driveshaft? Could that be the issue?

99% sure it's not a wheel bearing because it seems to be coming from the middle of the car, not any of the corners.

Anybody else have experience with this type of vibration?

 

Speaking from experience with my Honda Accord, mine turned out to be a inner CV driveshaft issue causing the vibration above 80km/h (50mph). No clicking noises, just constant mild shudder/vibration at higher speeds.

 

The symptoms sound the same as mine. Thanks for the input.

 

Did you do a road force wheel balance on your wheels?

 

It sure what a “road force” balance is so I’m guessing that’s not what Town Fair Tire did.

These are the original AMG wheels that came with the car. I did have all 4 of them straightened about a year ago (they described them as stop signs) but this is different than an out of round wheel.

 

Had similar issues with one of my old bmw. Vibrates at 70 to 75mph. Tried regular wheel balancing to no avail. Rotate wheel to rear to confirm it was the wheel causing the vibration. Took it to a Indy, he clean the wheel hub and use a Hunter road force balancing machine which is just a balancing machine that simulate highway speed which fixed 90% of my vibration. Slightly out of round wheels could cause a harmonic that results in vibration at certain speeds. Good luck.

 

Got it, thanks. I’ve recently found a great Indy and will be taking the car to him. I’ll use the info you provided to sound more intelligent.

 

To close this out....

The indy mechanic I found is incredible. Extremely knowledgeable. Loves Audis and BMWs because they keep him in business. His wife drives a Mercedes... He took it out for a road test with me aboard and he thought it was probably a bad rear tire. I wanted him to do a driveline inspection anyway so we booked that. He did a very thorough inspection and even brought me into the shop floor to show me what he looked at and the prognosis. By the way, the shop floor was spotless. The guy is meticulous.

Rear transmission mount shows some wear but he thought it could go another 20K to 30K miles. Flex packs were all in very good shape.

So what was it? Left rear tire has shifting belts. 3 weeks after getting it balance, it needed another 1.5 ounces of weight to get it back in balance. The tires are Continental PureContact (one of the quietest tires according to TireRack.com). And of course, Continental stopped making those but replaced it with the TrueContact. Tire shop guy said he couldn't tell them apart looking at the tread pattern. Same speed and load ratings. I know some are going to say that you have to replace all 4 tires because of treadwear differences mucking up the 4Matic. These tires had less than 5,000 miles on them (I run snow tires on separate rims for the winters here in northern New England). My mechanic said there would not be any issues.

The only bad news from this saga is that Continental will not reimburse me because I bought the new tire 6 days after the 1-year vibration warranty expired. I explained to the nice young lady on the phone that I had reported the vibration 2 months ago when I had the align and balance done (the report of vibration is in the notes section of the invoices) but she kept saying no. I'll write a letter to Continental to see if they will help but at least the tire store (Town Fair Tire in Keene, NH) knocked 25% off the price of the tire.

All's well that ends well....

 

FWIW, I had Pirelli Centurato P7 run flats on all four wheels. I have had to replace them because of side wall bubbles.

The last time I decided to go to Costco because of their 5 year road hazard warranty - which BTW would have covered your problem with the Conti's. I put Bridgestone Driveguard Plus RF on the rears, mainly because of their 60,000 mile warranty. I left the Pirelli P7 on the front. The tire depth on the front Pirelli's is 7/32 on the new Bridgestone's 9/32. I have driven over 5,000 miles with ZERO problems.

My opinion is that as long as the tires are high quality and the same size so the circumference is the same, (same number of revolutions per mile) there is nothing wrong with having brand X on the front and brand Z on the rear. Replacing all four tires when there is plenty of tread left on two of the tires is only good for the shop and/or dealer selling you the tires!

 

The Pirelli Cinturato P7 run flat size 245/45-19 tread depth is 10/32". The 245/24-18 tread depth is 8/32". What size did you have with 7/32"tread depth? How do the Bridgestone tires compare for noise, wet pavement handling, etc.? My local tire shop doesn't carry them, but a Chevrolet dealer does.

 

I have the standard tires: 245/45X18.

To be honest I really do not feel any difference between the Pirelli and the Bridgestone. I drive to Vermont many times a year and often run into snow and have had no problems.

When it rains I slow down and I drive moderately so handling and braking are just fine.

Also the Bridgestone's are about about $50 a tire cheaper than the Pirelli and I had three bubbles out of four tires with the Pirelli even though all the tires still had about 20K miles of tread life left. So I figured why not try another brand and see if I still get the bubbles.

Again the reason I went with the Bridgestone's are the 60,000 mile vs. zero for the Pirelli:

Hope this helps in your decision when it comes time to get new tires: Highly recommend Costco: they stand behind everything they sell - no questions asked!

This is from the Costco website:

 

Thanks for the recommendation. I noticed that the tire is a "member only item". I've never seen a Cosco let alone shopped at one.

 

When you sign in the price appears which is less than the published price.

If you a friend who is a member who should go with him. Shopping there is eye opening, plus everything they sell is guaranteed. On electronics for example, if there is a one year manufacturer's warranty, Costco doubles it to two years at no extra charge.

I had LED garland for Christmas decoration, 9 ft. strands. Two years later the LED did not light. Returned them for full credit! I bought a garden hose two years ago. The female connector did not work. Returned the hose, full refund!

Costco promotes from within. When you go the staff is often there for 5, 10 and even 15 years. Very, very friendly. Every employee gets full benefits including medical. Costco is usually one of the highest rated stores for customer satisfaction.

When you go, order the 1/4 hot dog and soft drink: free refills. $1.50 and it will never go up!

 

I,
2nd, 3rd and 4th that, I get everything from Costco, they are definitely #1 in my opinion. Then Amazon after 😊

 

OK, sure

 

Most of the time if there is an issue with vibration around above 70mph it is most probably tire/wheel balance related, unless there is a very obvious hub/CV/Axle issue.

Nice that you got it sorted. More than likely you will need to go back to the same Indy to balance any new tires out in the future as most generic shops will do the bare minimum to balance them and send you on your way.

On a sidenote, Costco for tires = Yes. I used Costco for my wifes Q7 (Michelin PS4's), and while the cost may be slightly higher than some, it includes install and a "road hazard" style warranty. The only thing that I would be concerned with is if you have nicer wheels, how they would handle them. I didn't worry so much about the wifes Q7 as she has already kissed the curbs on all 4 sides.

 

Does Cosco charge extra for the 5 year road hazard warranty or is that included in the price of the tire?

 

It is included.

 

Included in the price.