GLS550 rough ride
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Joined: Oct 2017
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2015 SL550, 2017 GLS 550, 2010 G550, 1995 E320 Cabriolet
GLS550 rough ride
My GLS 550 rides really rough.
47k miles. Well taken care of. I switched out the (nearly bald) stock Continental summer tires for slightly larger (315/30 R21) Continental AS and the ride is still rough. It shudders over rough roads. I don't remember it feeling like this this when it was new. What might be causing this?
47k miles. Well taken care of. I switched out the (nearly bald) stock Continental summer tires for slightly larger (315/30 R21) Continental AS and the ride is still rough. It shudders over rough roads. I don't remember it feeling like this this when it was new. What might be causing this?
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2023 GLE3502W, 2024 GLC3002W, 1967 Pontiac GTO 4 sp (sold...sniff)
Longshot and pardon me if this is too obvious. I have driven away from tire shops with a rough ride. Got home and checked the pressure. Once time the tires were 50+ psi when warm. This happened at least twice. Put a gauge on them.
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2015 SL550, 2017 GLS 550, 2010 G550, 1995 E320 Cabriolet
Do you mean I should reduce the pressure because they're around 50 right now...
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From: TX
2023 GLE3502W, 2024 GLC3002W, 1967 Pontiac GTO 4 sp (sold...sniff)
Check the pressure recommendations on the inside of the gas door. Lower the pressure to the lowest recommended number and see what the ride is like.
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2015 SL550, 2017 GLS 550, 2010 G550, 1995 E320 Cabriolet
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Joined: Sep 2016
Posts: 1,189
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From: TX
2023 GLE3502W, 2024 GLC3002W, 1967 Pontiac GTO 4 sp (sold...sniff)
Shouldn't matter. The max tire pressure is shown on the sidewall. According to what I could find, 50 lbs is the max for that tire. The minimum pressure is set by the car manufacturer. There is a range based on the weight that the tires will have to carry. Handling characteristics are very much a consideration when the range is established. If you're the only one in the car most of the time, reduce the pressure to the minimum on the sticker and see what that feels like. The rears on my wife's '23 GLE350 are 315/40-21. OEM. Pressure range is 31 to 44 lbs. Current warm pressure is 38 lbs. 50 is way too much.
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Joined: Oct 2017
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2015 SL550, 2017 GLS 550, 2010 G550, 1995 E320 Cabriolet
Shouldn't matter. The max tire pressure is shown on the sidewall. According to what I could find, 50 lbs is the max for that tire. The minimum pressure is set by the car manufacturer. There is a range based on the weight that the tires will have to carry. Handling characteristics are very much a consideration when the range is established. If you're the only one in the car most of the time, reduce the pressure to the minimum on the sticker and see what that feels like. The rears on my wife's '23 GLE350 are 315/40-21. OEM. Pressure range is 31 to 44 lbs. Current warm pressure is 38 lbs. 50 is way too much.
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Joined: Feb 2017
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From: Bigfork, MT, Castle Rock, CO
'21 M5Comp, '17 GLS450,'17 Range Rover, '08 Carrera 4S
30 series tires have next to no sidewall to absorb minor impacts as well.
That's the tradeoff for larger wheel diameter & shorter, stiffer sidewalls.
That's the tradeoff for larger wheel diameter & shorter, stiffer sidewalls.
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Thread Starter
Super Member
Joined: Oct 2017
Posts: 699
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2015 SL550, 2017 GLS 550, 2010 G550, 1995 E320 Cabriolet
Thread Starter
Super Member
Joined: Oct 2017
Posts: 699
Likes: 149
2015 SL550, 2017 GLS 550, 2010 G550, 1995 E320 Cabriolet
I aired them down from 48 to 38. Unfortunately they warmed back up to 42 on my 120 mile highway round trip today. The ride was marginally better but still not great. I’m going to bring them down to 35 and see if that helps. That said, I can’t help but think something else is wrong.
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Joined: Feb 2017
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From: Bigfork, MT, Castle Rock, CO
'21 M5Comp, '17 GLS450,'17 Range Rover, '08 Carrera 4S
Looking at your profile, I've got to trust your butt-o-meter. Do you have a shop you trust who could send someone to ride along with you?
There's nothing like a second opinion.
There's nothing like a second opinion.
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Joined: Dec 2007
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From: ATL
2017 GLS 550
So, lets narrow it down a little. Did you buy it new? Did you buy used? Has it been rough since day 1 of your ownership. have you checked all your bushings for tears/separation? Did the tire shop do a roadforce balance, with these big heavy wheels and tires, often times the yellow dot lining up with the valve stem isn't always the best placement of the wheel.
