RoadVitals

2018 Mercedes-Benz GLS 550 Problems

Owner-reported complaints filed with NHTSA, grouped by component

Data refreshed

Owner complaintsComplaints are reports submitted to NHTSA by owners and drivers. NHTSA does not verify most reports before publishing them, and a complaint does not establish that a defect exists. Volume is influenced by how many of a vehicle were sold, how long it has been on the road, and how much attention an issue has received.
6
Latest Jul 6, 2026
Components namedHow many of our component categories appear on at least one report for this model year. One report can name several.
6
Crash or fire reportedComplaints whose submitter recorded that a crash or a fire occurred. These are the reporter's own answers on the NHTSA form, not verified findings.
0

What this page shows

Everything below is an owner-reported complaint submitted to NHTSA about the 2018 Mercedes-Benz GLS 550, grouped by the component NHTSA recorded on the report. These are not confirmed defects, and they are not recalls. NHTSA does not verify most reports before publishing them, and a category with more reports in it is not evidence that a part is defective.

Complaints are reports submitted by owners and drivers to NHTSA. They are not verified and do not establish that a defect exists.

Reports by component

Ranked by how many owner reports name each component category

  • Brakes116.7%
  • Electrical116.7%
  • Powertrain (other)116.7%
  • Seat belts116.7%
  • Suspension116.7%
  • Visibility116.7%

Percentages are of component mentions. A single complaint can name more than one component, so these do not sum to the total complaint count.

Each component in detail

What the reports in each category say, in the owners' own words

Brakes

Reports naming service brakes, the antilock braking system, brake hoses, master cylinders or the parking brake.

1
report

From owner reports, verbatim

The contact owns a 2018 Mercedes Benz GLS550. The contact stated that when the brake pedal was depressed there was an abnormal noise detected. The brake warning indicator light was illuminated. The contact stated that the brake pad on one side of the disc was completely worn, and the other side of the disc was like new with a full thick pad. The vehicle was taken to the local dealer and the contact was informed that the brake rotor needed to be replaced. The vehicle was repaired. The manufacturer was notified of the failure however, no further assistance was provided. The failure mileage was approximately 4,500. Consumer stated problem lies with the unevenness of the brake pad on both sides of the front wheels.

NHTSA ID 11429716 · filed Aug 19, 2021

Too few reports in this category for a page of its own — they appear in the full complaint list.

Electrical

Reports naming the electrical system — wiring, battery, charging, control modules, infotainment and electrical accessories.

1
report

From owner reports, verbatim

SEATBELT HAD TIGHTENED AND NOT RELEASED WHEN MY BODY MOVES. BRAKES ARE NOT APPLIED. TYPICALLY DURING DRIVING I'M SMALL ENOUGH TO MANEUVER MY HAND DOWN TO RELEASE RED SEAT BELT BUTTON. *TR I'VE HAD TO STOP MY VEHICLE 5-10 TIMES TO RELEASE BELT. I HAVE 2 SMALL KIDS 7/ 11 BOTH ARE 60 POUNDS THEY ARE 4 FEET TALL AND 4'6' 7 YEAR OLD STILL USES BOOSTER I''VE CHECKED BELTS TO THE BEST OF MY ABILITY BUT I'M 110 LBS 5'2' AND HAVE NO MECHANICAL TRAINING OR EXPERIENCE OR CERTIFICATIONS THIS HAS BEEN NOTED TO MERCEDES AND THE PROBLEM IS NEVER REALLY DISCUSSED. THE VEHICLE WAS OPERATING UNDER ALL CONDITIONS NOTED BELOW

NHTSA ID 11297292 · filed Jan 6, 2020

Too few reports in this category for a page of its own — they appear in the full complaint list.

Powertrain (other)

Powertrain reports that are not specifically the engine or transmission — driveshafts, axles, transfer cases and differentials.

1
report

From owner reports, verbatim

WHILE IN MOTION ON A HIGHWAY IN STOP AND GO TRAFFIC, CAR SHIFTED ITSELF FROM DRIVE TO NEUTRAL WITHOUT ANY DRIVER INPUT. ALL INDICATOR LIGHTS ON DASH TURNED ON. DRIVER UNABLE TO SHIFT FROM NEUTRAL BACK TO DRIVE TO REGAIN CONTROL OF VEHICLE. DRIVER COULD ONLY SHIFT TO PARK. DRIVER SHIFTED VEHICLE TO PARK AND TRIED TO SHIFT TO DRIVE, BUT WAS UNABLE TO DO SO. DRIVER TURNED OFF IGNITION AND RESTARTED CAR, AT WHICH POINT DRIVER WAS ABLE TO SHIFT THE VEHICLE INTO DRIVE. DRIVER REPORTS NO USER ERROR (I.E. DID NOT ACCIDENTALLY HIT THE SHIFTER, DID NOT HIT ENGINE ON/OFF BUTTON) AND NO INDICATOR LIGHTS WERE PRESENT PRIOR TO INCIDENT. VEHICLE WAS BRAND NEW: OWNED FOR APPROXIMATELY 10 DAYS WITH 199 MILES AT THE TIME OF ACCIDENT. VEHICLE HAD BEEN PURCHASED WITH 6 MILES ON ODOMETER.

NHTSA ID 11101953 · filed Jun 14, 2018

Too few reports in this category for a page of its own — they appear in the full complaint list.

Seat belts

Reports naming seat belts, buckles, retractors and pretensioners.

1
report

From owner reports, verbatim

SEATBELT HAD TIGHTENED AND NOT RELEASED WHEN MY BODY MOVES. BRAKES ARE NOT APPLIED. TYPICALLY DURING DRIVING I'M SMALL ENOUGH TO MANEUVER MY HAND DOWN TO RELEASE RED SEAT BELT BUTTON. *TR I'VE HAD TO STOP MY VEHICLE 5-10 TIMES TO RELEASE BELT. I HAVE 2 SMALL KIDS 7/ 11 BOTH ARE 60 POUNDS THEY ARE 4 FEET TALL AND 4'6' 7 YEAR OLD STILL USES BOOSTER I''VE CHECKED BELTS TO THE BEST OF MY ABILITY BUT I'M 110 LBS 5'2' AND HAVE NO MECHANICAL TRAINING OR EXPERIENCE OR CERTIFICATIONS THIS HAS BEEN NOTED TO MERCEDES AND THE PROBLEM IS NEVER REALLY DISCUSSED. THE VEHICLE WAS OPERATING UNDER ALL CONDITIONS NOTED BELOW

NHTSA ID 11297292 · filed Jan 6, 2020

Too few reports in this category for a page of its own — they appear in the full complaint list.

Suspension

Reports naming suspension components — springs, struts, shocks, control arms and related hardware.

1
report

From owner reports, verbatim

The contact owns a 2018 Mercedes-Benz GLS 550. The contact stated while driving at various speeds, the vehicle made an abnormal clicking sound when making a right turn, and an abnormal ticking sound at startup. There was no warning light illuminated. Another driver informed the contact that the front passenger-side wheel was loose and followed the contact to the residence. The vehicle was taken to a local dealer, where it was diagnosed that the sway bar needed to be replaced; however, the sway bar was only adjusted. The contact stated that the failure had recurred. The dealer was notified and informed the contact that the vehicle was safe to drive. The manufacturer was contacted and advised that any additional repairs would be at the owner's expense. The contact was referred to the NHTSA Hotline for assistance. The failure mileage was approximately 75,045.

NHTSA ID 11748540 · filed Jul 6, 2026

Too few reports in this category for a page of its own — they appear in the full complaint list.

Visibility

Reports naming windshields, glass, wipers, defrosters and mirrors.

1
report

From owner reports, verbatim

Water collects at the front row floor at driver and passenger sides

NHTSA ID 11576448 · filed Mar 10, 2024

Too few reports in this category for a page of its own — they appear in the full complaint list.

Higher-selling and older vehicles accumulate more reports. Counts are not failure rates and are not directly comparable between vehicles that sold in very different numbers.

Elsewhere on this vehicle

Data sources

Data on this page last refreshed .