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Had my GL63 to the dealer a few weeks back as it was starting to feel very unsettled in the corners, stepping out in the rear wheels at times and even on straight runs felt like she was moving around.
Dealer didn’t do full diagnostic but did notice that the fluid level was low on the air suspension system so topped up and she felt a lot better, more engineered and controlled.
Last week or two its started stepping out on occasion and feeling unsettled again and looking at the tyres tonight theres some very obvious rubbing marks on the sidewalls on all 4 tyres that could explain why she’s feeling unsettled but is it likely that all 4 tyres sidewalls are flexing this much, one tyre ok, all 4, really?
All 4 tyres 6mm Pirelli P Zero MO spec 295/45/21 on factory rims.
Anyone seem this kind of thing before? Im going to speak to th local MB dealer but expect them to say its the tyres, and quote for 4 new ones so wanted some ammunition if its available?
Hi, i can see why you would think that but honestly its not kerb scuffs. Ive noticed it recently, more obvious this past few days and Im 100% sure Ive not scuffed the tyres.
Tonight I took a turn at around 25mph and literally felt the back step out like theres no grip so Im starting to think the sidewalls on the tyres are flexing but only at certain points, as if the grip goes. I had to pull over one day, it felt like I was riding on ice but it was a sunny and dry day.
Is it feasible that the marks are because of sidewall flex, what else could explain all 4 tyres and the funny let go feeling?
16 E550 Cab, 2003 Ram bright red crewcab 4x4 we call Clifford :)
HHHMMMmmmmmm, did ya go over a speed bump at speed perhaps ? maybe crush the cords in those spots ? what your describing sounds like a weak sidewall or woefully under pressurized tires ? 39 psi.... cold or hot ? i run at 45 or so but i would not think 39 would roll ? you say all 4 tires have those marks ? kids borrow the car recently and do a ferris buehler ?
No to the speed bumps, 39 cold as recommended by others on here and Im the only driver of the vehicle.
45 sounds high, the fuel flap says 36 all round so 39 has been used for a few weeks, thats one thing in common I guess?
The marks are in patches rather than radial in the way you’d expect if I ran the wheel around a kerb for example and the ride feels unsettled a fair bit, very unsettled occasionally so Im thinking the tyres are giving up but it just doesn’t make sense
Each tyre has a different amount of marking, all randomly placed, worst affected is the right side rear one which is strange, the vehicle stepped out turning right tonight so the left rear would have the most marking on it in that case Id expect?
Im going to clean and dress them with high end tyre product and watch to see if it comes back with general driving.
I guess my bigger question is why is the car still feeling unsettled, will have to get the tyres balanced and bushes checked I think.
How could you be "riding on your sidewalls" so that the wear pattern reaches almost to the wheel? The tires may be properly inflated, but the sidewalls appear not stiff enough to support the vehicle. Do they bulge when the vehicle is stationary?
If your tires are rolling onto their sidewalls while cornering that seems a serious problem. As all four tires have the problem it seems they are not the right tires for your vehicle.
Please post more pictures after you have cleaned and dressed the tires.
No bulges when stationary, they’re definitely the right tyres for the vehicle, I cant believe they move that much on the rims, its just a completely crazy theory but the vehicle steps out now and then and feels unsettled even on highways at times, I actually drive in Sport + to stiffen the ride and refuce the floaty rolling feeling
I cleaned and dressed the sidewalls after having the tyres removed and remounted. During the remounting the tyre guy used one of the Hunter machines to massage the bead which centred the tyre on the rims apparently, its helped it feel more sure footed now.
I did get a couple of marks on the left side tyres but nothing like before, but I still dont believe they tyres moved so much that it marked the sidewalls.
That's curb rash or your vehicle is bottoming out (highly doubtful). Oh yeah, is your sidewall failing I had that happen on those cheap Conti DSW's on a C-Class Sport?
I agree ... DC-Benz, those are curb marks on the sidewalls. Notice how they swirl, which indicates they are made by a stationary object as the tire scrubs against it. If it was from the road the marks would be parallel to the tread and all around the tire. Each mark in the photos is from a discrete impact rather than continuous contact. Some are so severe that I wonder if they are from curb jumps rather than scrubs!
Considering the severity of these impacts I would be concerned that the sidewalls have been compromised, which would explain the "stepping out" phenomena described by the OP.
I don't think so, it looks just like someone was parallel parking. They back in until their front tire rubbed then rubbed again when they pulled forward to straighten out.
2010 Mercedes GL450; 2000 Mercedes ML55 AMG; 2016 VW GLI SEL Stick!!!
haha,no I agree the tire marking looks like curb rash;
I mean the op original complaint about feeling unsettled in corners and not feeling very stable on the straights. He mentioned that early on, isnt that perhaps a symptom of a defect in the active curve system?
I did some tests with the tyres and found that its from going onto a kerb, literally very slowing putting 2 wheels up the kerb to park (common here in the UK).
Im surprised that the tyre can be scrubbed at such speeds but after cleaning up then doing it the marks reappeared.
Still doesnt explain the insettled ride, I think its better at 39 all round but still think it has a dual character, feels great one day and unrefined another. Its done mid 60k miles now, I use it every day for business and pleasure so maybe struts, bushes etc are worn out?
MB dealers here are really poor, they wont spend the time to figure this kind of stuff out.
Well your tires are pretty close to the wear bars and it looks like you drive pretty aggressively so get a new set and report back. Pirellis don't get better with age.
Originally Posted by carlosamg50
Hi all
I did some tests with the tyres and found that its from going onto a kerb, literally very slowing putting 2 wheels up the kerb to park (common here in the UK).
Im surprised that the tyre can be scrubbed at such speeds but after cleaning up then doing it the marks reappeared.
Still doesnt explain the insettled ride, I think its better at 39 all round but still think it has a dual character, feels great one day and unrefined another. Its done mid 60k miles now, I use it every day for business and pleasure so maybe struts, bushes etc are worn out?
MB dealers here are really poor, they wont spend the time to figure this kind of stuff out.
2010 Mercedes GL450; 2000 Mercedes ML55 AMG; 2016 VW GLI SEL Stick!!!
Yeah, your tires are low in tread and considering how often you've hit the curb and the low profile tires the structural integrity of the tire or even the rim may have been compromised.
It certainly is the cheaper option.
That being said; you said the dealer said your airmatic fluid was low and refilled it. That's impossible. The only thing that needs to be refilled is the oil on the active curve system and that often has issues with air in the system. Furthermore you said it felt better after it was refilled; and only later did the symptoms return.
I would ask your dealer to bleed out the lines of the active curve system to get out the air (common problem with acs); and if problems still exist it might be the tilt sensor (also a common problem).
Your problems, from how you describe them clearly stem from the active curve system; the tire marks might be a happy coincidence.
Hi, tyres are a good 5-6mm, plenty of life in them yet. I will avoid riding up the kerbs from now on, Ive never allowed the tyre to hit the kerb but will stop in any case.
Thanks for the info relsting to ACS, I didnt know that the top of of fluid was questionable, it did feel very different right after it happened and now its a bit hit and miss, often after a short journey a restart for the next journey gives an improved feel in ride quality.
05-22-2018, 01:26 PM
