Dog hauler

My 2914 GL350 has a fairly subtle vibration that starts at about 70 mph. The vibration isn't through the steering wheel and has nothing to do with the brakes (it's not a warped rotor problem). The tires were road force balanced my my tire shop and the vibration remains.

I took the car to the dealer who agrees there is, indeed, a vibration that shouldn't be there. They re-balanced the wheels (road force again) but that had no effect. They then switched wheels/tires with a new GL on their lot. No luck. The vibration is still present. The dealer still has the car and will investigate further come Monday.

Does anyone have any ideas on what could be causing the vibration?

Nihsel10

My guess would be from the 7G transmission and the drivetrain. Have them inspect the torque converter and transmission.

also, do you feel any "jerkiness" from the gear shifts? They are usually the first signs before the vibration kicks in.

Dog hauler

I don't feel any jerkieness that I think could be related to the vibration. When slowing gradually and smoothly to a stop, the 4 > 3 downshift is not smooth. It's not a toss your head forward jerk, but it's not smooth. I complained about this long ago, but the dealer claims they don't feel anything unusual on test drives...they must usually drive Yugos, but that's another story.

The vibration I'm talking about here starts right around 70 mph: I can cruise along around 65 without vibration then gradually accelerate without downshifting from 7th gear to 6th and when I hit right around 70, the vibration kicks in.

mtm

Have you tried shifting to neutral past 70 mph to see if the vibration is still there? That would help to see if it's drivetrain related.

Dog hauler

Haven't tried that. But even in neutral, the driveshaft, half-shafts and diffs are still spinning so I'm not sure what the neutral thing might tell me. It can't hurt to give it a try, though. Thanks.

mtm

I shouldn't have said drivetrain - meant to say to isolate engine and transmission from the rest of the powertrain/drivetrain

Dog hauler

Will give it a try.

SFML320

Sorry to read this is happening to the GL350 too. Did you change out your OEM tires by any chance before you started to feel the vibrations? That is what happened to our GL450...was very smooth at any speed until I had to change out the OEM Scorpions.

You can read more here: https://mbworld.org/forums/gl-class-...ml#post6549693

fabbrisd1

I would recheck tire pressure and try 2lb +/- front and back - and see if "vibration" changes speed/tone-frequency

Dog hauler

Yes, new tires were installed but the swap was with the very same as OE, Continental something or others. The vibration was present before the swap and after, despite road force balancing by a shop I've been using without issue for years (and which was originally recommended by Tire Rack) and re-balancing after the vibration was still present after the installation of the new tires.

The dealer called this morning after having the car since Friday. Per SA: the first thing tech did was road force balance the tires. No change to vibration. Next they swapped wheels/tires with a new GL in inventory. No change. Then to a second set of new wheels/tires from a different inventory GL. No change.

Then must head scratching, examining of various parts and calls to MBUSA. No good ideas.

Then, the tech thought "hmmm. Maybe the inventory tires were flat-spotted from sitting on the lot. I'll get a 3d set from a GL that hasn't been in inventory for long so that flat spotting can't be a problem." With that done, the vibration is supposedly gone and they believe that flat spotted tires from the inventory GLs were the problem. The SA asked me to come in and the tech and I will take the car for a ride to see if, indeed, the vibration is gone.

Well, let's just say I'm skeptical. The vibration was present with the old tires and it was present with the replacement tires despite road force balancing of those tires both when they were installed and by the dealer just now. Those tires wouldn't have had flat spots.

And to think that two different sets of inventory tires from brand new GLs were flat spotted seems a stretch. And even if they were, we get back to my replacement tires (not to mention the OE tires) could not have had flat spots from sitting. In any event, my tire shop tells me that road force balancing would immediately detect any flat spots...the machine, Hunter GSP 9700, would read out that the flat spotted tire needed replacement. And let's not even mention that the dealer road force balanced my wheels/tires and their machine didn't detect any flat spots or other abnormalities, though I don't know what equipment they have.

Anyway, I'm headed to the dealer now for a test drive with the 3d set (non-flat spotted) inventory wheel/tires to see if I agree the vibration is gone. I'll reserve judgment until going for a drive, but the flat spot scenario just doesn't make any sense.

Fabbrids1: since having my OE tires replaced a while ago, I've varied the pressure depending on the type of driving, such as around town, sustained high speed, and trailer towing. There's been no change to the vibration.

Dog hauler

This is something I never expected: No, it's not flat spotted tires...that much was expected. But it is the tires and/or wheels and there's much more to the story that was completely unexpected.

I get to the dealer and the "Team Leader" is the fellow I'm dealing with. He's a nice guy who seems to care. As I understand it he is the head technician who is charged with figuring out the tougher cases while the rest of the techs perform more routine repairs. Anyway, he tells me that he's pretty sure the problem is the 19" wheel/tire combination. Not just my set. All of the 19s on GLs, with the 20s and 21s not having the vibration.

Upon hearing this, I thought "yea, right. I've heard 'they all to that' before." But, he had my truck fitted with a set of 20s with Pirelli Scorpions off a new inventory GL and suggested I take it for a drive. As I'm driving along, I'm thinking that the vibration is much, much less than with my 19s but because the vibration even with the 19s is fairly subtle I'd like to get my 19s back on for a back-to-back comparison. So I return to the dealership and the tech refits my 19s and off I go on the same route. Holy cow! My 19s clearly cause a bigger vibration (by a wide margin) than the 20s even though I had the 19s road forced balanced with I first fitted them to the truck and the dealer road forced 'em again first thing when he started looking into the problem. But wait, there's more.

I get back to the dealership again and the tech suggests I take out one of the inventory GLs fitted with 19s, so I do. The tech previously drove 4 of the inventory GL on the lot and he told me that each of them has the vibration I'm complaining about and a couple of the inventory units are worse than mine. I told him I wanted to go out in the GL with 19s and the least vibration. I'm looking over his shoulder while he checks his notes so I see he really does pick the one with, according to his notes, the least vibration and off we go.

As I may have mentioned: holy cow! The inventory unit has the same vibration as does my car and to the same degree. With 4 different brand new inventory GLs with 19s all having the same vibration as my truck (some are worse and none was better) it must mean that there is something about that wheel and tire combo that's causing the vibration that no amount of balancing will cure. I can't imagine what that is, though. If the either the wheel or tire were out of spec, the road force balance would detect it and, in any event, it seems pretty much impossible that each of 4 sets of brand new wheels and tires, plus my set, would have one or more corners out of spec. That would just be too much of a stretch.

The 20s drove smoothly and 5 sets of 19s didn't so the bottom line seems to be that there is an inherent vibration issue with all 19s. And MB sells the 19s to customers anyway. That kind of ticks me off. Not at the dealer, but at MBUSA.

The other part of the bottom line is that I can either put up with the vibration or I can buy new wheels and tires for... what...maybe $4-5k? That really pisses me off.

At least the dealer did a good job of figuring out the problem and taking the time to not only explain it to me, but to show me first hand. Had the tech or the SA merely called me and said "your truck sure enough has a vibration, but it's caused by your wheels and tires...all 19s do that," I wouldn't have believed them and I'd have been pretty unhappy.

In the past, including in this thread, I've disparaged MBs customer service. I stand by that, but in this instance (and for the most part with one notable exception) my dealer's customer service is good. MBUSA is another story and the fact that they're selling GLs with an inherent vibration problem doesn't help my opinion.

I'd like to hear from others out there with 19s as to whether they feel a vibration at 70 mph and up. You need a fairly sensitive butt to feel it and a stretch of very smooth pavement to tell it's the car generating the vibration and not the pavement.

mtm

What a story!

Now here's a kicker - I have almost the same story, but with 20" wheels and Pirelli Scorpion Verde tires.

Original set had vibrations between 60-70 MPH. Road Force balanced at the dealer. Same vibration.

Replaced all four tires with same Scorpion Verde and Road Force balanced. Same vibration.

Replaced with a second set of Scorpion Verde and Road Force balanced. A little better, but still some vibration.

Replaced with Bridgestone Dueler H/L - vibration gone.

According to shop foreman the 20" wheels and Pirelli Scorpion Verde combo is a common problem for them.

Two different brand new ML loaners I had in the meantime had 20" AMG wheels - one with Pirelli Scorpion Verde had same vibration as mine. The other with Continental tires had no vibration at all.

43221B

I had the same issue with the 20" Scorpion's on my '14 450 and my advisor told me the same thing. I ended up switching to Continental summer tires to resolve the vibration. What I learned is that the tires don't just have to be within spec on the roadforce balancer, they have to be significantly within spec. The 450 is proving to be notoriously difficult to balance tires on for the dealerships.

What I find curious is that my dealership went through this early in 2014 with my '14 450. It was sort of a known issue back then. Why are some of the dealerships acting like they've never heard of this? Don't the dealerships communicate through service bulletins etc?

mtm

One immediately obvious difference between Pirelli and Bridgestone is that although they are the same size, the footprint of Pirelli is quite a bit wider.

I wonder if that could have something to do with it?

just checked the specs on tirerack:

Pirelli tread width is 10.7" vs Bridgestone's 9.2" vs Conti's 9" vs Michelin's 9.4"

43221B

I have a 550 now with even wider tires and it's smooth. After trying a few sets of Pirellis on my 450, all very close to the limits of being within spec, I think the tire cos are just shipping out large batches of poor quality tires and it doesn't sound specific to any one brand. Perhaps if you try several tires that came off the same assembly line over the same few weeks period of time, you are going to get the same quality problem. I called mbusa and expressed my dissatisfaction with them shipping cars from the factory with unbalanced tires on them. Doubt that did any good though.

aeggroup

I have 2015 GL350 with 19". Tires are Contis. My car has almost 14K miles, no ANY vibration noticed at any speed.

cadetdrivr

Ditto here with a '14 GL350 with 19" wheels and Continentals. I'd like to think that my backside is pretty attuned to sensing undesired vibration.

I wonder if there is something else going on here? (Certain production dates for wheels or tires? Or certain combinations of production dates?)

I'm glad Dog hauler had a dealer that was willing to go the extra mile to find the cause.

Elric99

I have a '14 450 w/ 20" wheels and it has always had a mild vibration at 70 mph. After various tests of tire combos, and driving another 450 on the lot w/ 20" wheels that had similar issues, it really seems to me luck of the draw. Some combos of wheels+tires have it worse than others. You can buy a new set of 20" wheels, but they may very well have the issue. Perhaps you can get the dealer to guarantee they will take them back if they vibrate?

Dog hauler

Dealer claims that they're talking with MB to see if anything can be done for me under warranty. It's been 3 or four days now with no word. I'm not holding my breath.

Ironically, they tell me that because I didn't complain about it right off the bat (or at least within the first year) MB is less likely to do anything. But after being brushed off by the dealer and MB in connection with a complaint I had early on about less than smooth 4 > 3 downshifts, I didn't see much percentage in complaining about the vibration until it finally pissed me of enough. All they need to do is drive any of the GLs with 19s that are on the lot. They all do the same thing and that's according to the Team Leader tech (see story above).

Shawnasy

Both my 2012 and 2016 which is currently in the shop having tires put on have the exact same problem. It is terrible and not fixable in my oppinion, gas one seemed better.

43221B

I've had a 13 and 15 GL. Both have had wheel/tire vibration issues. The fix is finding tires that are well within spec on the Road Force balancer. The GL is extremely sensitive to tires that are out of round. I have a 15 GL550 and the tires have vibrated for probably 40,000 of the 60,000 miles I've driven it and I've had the dealership replace the tires. Trust me, it is the tires. For this reason I will probably never purchase another SUV that is this expensive. It doesn't make sense to spend so much on a vehicle that vibrates at freeway speeds. Mercedes either needs to make the suspension less sensitive or they need to expect more from the tire manufacturers. Hopefully the guy with the white mustache will read this, but I doubt it.

DaveW68

Wayne Carini or Colonel Sanders?

kombifan

jbattan

ejbenson

I, too, had vibration issues that manifested just over 70 mph. Initially I thought this is just how it is. As part of the sale of the used vehicle I requested new tires and a Service B w/ Brake Fluid Flush. They agreed and it was like a new car after that. Drove like a dream.

Anecdotally, I had a 1987 300E back in the day that had a vibration similar to what you are describing. Though, it sounds like you've narrowed it down to the tires/wheels potentially. But the 300E had a bad bearing in the driveline that went from the transmission to the rear wheels (straight 6, RWD sedan). After replacement it pulled very well without any vibrations. May want to double check bearings of all kind as that can cause the car to vibrate as well depending on where it/they are located and their level of degradation. Just a thought, might be a wild goose chase but something to ponder if all else fails. Also depends on mileage, I didn't read EVERY post but I didn't see any mileage listed on your vehicle on a cursory review of the postings. I hope this helps if all else fails.

I agree with earlier posts, it could be transmission related. I have had transmissions that have benefited greatly from a flush, filter change, draining the torque converter, and sometimes doing that followed by a simple fluid change about 5-10K later just to make sure all the crap is out of the transmission. You may also check with a local specialty shop as there are transmission service devices that they can hook in-line with the transmission cooling line that will pump 25-30 quarts of fluid through the transmission while the car is parked/running which can sometimes get more crap out of the whole system then just a gravity based drain. Food for thought.