Owners have filed 16 complaints
about the 2023 Mercedes Benz GLS 450 4MATIC with NHTSA between 2023 and 2025.
The largest single group is the brakes.
Across this model's run it ranks 4 of 4 worst.
The letter says how bad. This says what kind — whether this year drew
an unusual number of complaints, unusually dangerous
ones, or failures that arrived unusually early.
The dashed ring is 50 — the national norm. Further out is worse.
Complaint volume — 42
Against the median year of the Mercedes Benz GLS 450 4MATIC. 50 means typical for this
model; 100 means roughly double.
Severity — 0
0% of these complaints
involved a crash, fire, injury or death, against a national rate of
9.7%.
Early failure — not reported
Too few complaints recorded a mileage to measure this.
How 2023 compares with every other Mercedes Benz GLS 450 4MATIC
Complaints filed with NHTSA, by model year. Bar colour is the FaultScore grade:
A
B
C
D
F
ungraded
What breaks on a 2023 Mercedes Benz GLS 450 4MATIC
Every complaint is filed against a part. Follow any row for the complaints about that part alone.
Driver Assist & Collision Avoidance
425.0%
Brakes
425.0%
Engine & Cooling
318.8%
Fuel & Propulsion
212.5%
Median failure at 11,000 miles
Other & Unspecified
16.3%
Wheels
16.3%
Electrical System
16.3%
When owners complained
A spike years after the car went on sale usually means a part wearing
out on schedule across the whole fleet — the kind of pattern no single
owner can see from inside their own car.
May 2023peak 3Apr 2025
The most recent complaints
In the owners' own words, exactly as filed with NHTSA.
Hampden, ME
SERVICE BRAKES
The car recently underwent a software update at the dealership for a backup camera issue. When I was driving home on the highway, the car suddenly braked and the seat belts automatically tightened up. This happened 3 additional times on the highway about 5 days later. I had turned off the automatic braking system and it seemed to go away. Then, with the system off, we experienced this again yesterday while on the highway at 70mph. The braking lasts for 1-3 seconds. There is no audible alert or dashboard display. IT renders the car quite unstable as it feels as though the rear brakes are being activated before the front. I reported this to the dealership and they want to inspect the car.
NHTSA complaint #11654449 — an unverified report by a vehicle owner.
The car recently underwent a software update at the dealership for a backup camera issue. When I was driving home on the highway, the car suddenly braked and the seat belts automatically tightened up. This happened 3 additional times on the highway about 5 days later. I had turned off the automatic braking system and it seemed to go away. Then, with the system off, we experienced this again yesterday while on the highway at 70mph. The braking lasts for 1-3 seconds. There is no audible alert or dashboard display. IT renders the car quite unstable as it feels as though the rear brakes are being activated before the front. I reported this to the dealership and they want to inspect the car.
NHTSA complaint #11654449 — an unverified report by a vehicle owner.
Purdon, TX
SERVICE BRAKES
There have been 3 incidents where the car responded to unknown stimuli by braking hard. 3 months ago it happened while making a left turn through an intersection, driving about 10 mph the brakes unexpectedly locked up, luckily the person behind me took evasive action and didn't hit me; 2 weeks later it happened again, I was driving on I-45 attempting to pass slower drivers, the brakes dramatically engaged while I was driving over a slight hill, today it happened again when it mistook a vehicle in a different lane of traffic, and performed a hard brake evasive measure even though there was no chance of collision and nothing in front of the vehicle.
NHTSA complaint #11617794 — an unverified report by a vehicle owner.
Purdon, TX
FORWARD COLLISION AVOIDANCE: ADAPTIVE CRUISE CONTROL
There have been 3 incidents where the car responded to unknown stimuli by braking hard. 3 months ago it happened while making a left turn through an intersection, driving about 10 mph the brakes unexpectedly locked up, luckily the person behind me took evasive action and didn't hit me; 2 weeks later it happened again, I was driving on I-45 attempting to pass slower drivers, the brakes dramatically engaged while I was driving over a slight hill, today it happened again when it mistook a vehicle in a different lane of traffic, and performed a hard brake evasive measure even though there was no chance of collision and nothing in front of the vehicle.
NHTSA complaint #11617794 — an unverified report by a vehicle owner.
There have been 3 incidents where the car responded to unknown stimuli by braking hard. 3 months ago it happened while making a left turn through an intersection, driving about 10 mph the brakes unexpectedly locked up, luckily the person behind me took evasive action and didn't hit me; 2 weeks later it happened again, I was driving on I-45 attempting to pass slower drivers, the brakes dramatically engaged while I was driving over a slight hill, today it happened again when it mistook a vehicle in a different lane of traffic, and performed a hard brake evasive measure even though there was no chance of collision and nothing in front of the vehicle.
NHTSA complaint #11617794 — an unverified report by a vehicle owner.
Holly Springs, NC
ENGINE
when coming to a stop and applying the break, the transmission stalled. a warning was issued around lane keeping assist and a second warning. Then the transmission light was on. It was not at risk in the moment because no one was behind me and I was coming to a stop sign. If it prevented me from stopping I might have gone through the stop sign It is at the dealership today to service. no warning lamps, messages or other symptoms.
NHTSA complaint #11609931 — an unverified report by a vehicle owner.
Holly Springs, NC
SERVICE BRAKES
when coming to a stop and applying the break, the transmission stalled. a warning was issued around lane keeping assist and a second warning. Then the transmission light was on. It was not at risk in the moment because no one was behind me and I was coming to a stop sign. If it prevented me from stopping I might have gone through the stop sign It is at the dealership today to service. no warning lamps, messages or other symptoms.
NHTSA complaint #11609931 — an unverified report by a vehicle owner.
Holly Springs, NC
LANE DEPARTURE: ASSIST
when coming to a stop and applying the break, the transmission stalled. a warning was issued around lane keeping assist and a second warning. Then the transmission light was on. It was not at risk in the moment because no one was behind me and I was coming to a stop sign. If it prevented me from stopping I might have gone through the stop sign It is at the dealership today to service. no warning lamps, messages or other symptoms.
NHTSA complaint #11609931 — an unverified report by a vehicle owner.
at 11,000 milesFranklin, NC
FUEL SYSTEM, GASOLINE
The contact owns a 2023 Mercedes-Benz GLS450. The contact received notification of NHTSA Campaign Number: 23V880000 (Fuel System Gasoline) however, the part to do the recall repair was unavailable. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was made aware of the issue. The contact stated while driving approximately 10 MPH and making a left turn, the vehicle stalled. The contact stated that an unknown warning was illuminated; however, when the vehicle was restarted, the warning light was off. The vehicle was taken to a dealer who was unable to duplicate the failure. The vehicle was not repaired. The contact stated that the failure reoccurred after receiving the recall notification. The failure mileage was approximately 11,000. Parts distribution disconnect.
NHTSA complaint #11604201 — an unverified report by a vehicle owner.
Glen Carbon, IL
ENGINE
Twice the vehicle has stalled while driving. I see that there is a recall on my model for a faulty fuel pump which causes this problem, but my dealer claims my vehicle is not part of the recall even though it is having the same issue.
NHTSA complaint #11548136 — an unverified report by a vehicle owner.
Glen Carbon, IL
FUEL/PROPULSION SYSTEM
Twice the vehicle has stalled while driving. I see that there is a recall on my model for a faulty fuel pump which causes this problem, but my dealer claims my vehicle is not part of the recall even though it is having the same issue.
NHTSA complaint #11548136 — an unverified report by a vehicle owner.
Hurst, TX
ELECTRICAL SYSTEM
I have a new GLS450 and on two separate occasions the car has shut down at a stop with no warning. First time was approximately mid July of 2023 with about 1,700miles. While at a stop the instrument panel displayed a text box with the words “Malfunction” across the screen, and proceeded to shut down. After a minute we were able to restart the car. Took it back to the dealership and they were not able to get any codes or reason why it happened. Now 3 weeks later it happened again, and back at the same dealership from where I purchased it. Again, same story that they are not able to get any codes as to what malfunctioned.
NHTSA complaint #11537552 — an unverified report by a vehicle owner.
Hurst, TX
ENGINE
I have a new GLS450 and on two separate occasions the car has shut down at a stop with no warning. First time was approximately mid July of 2023 with about 1,700miles. While at a stop the instrument panel displayed a text box with the words “Malfunction” across the screen, and proceeded to shut down. After a minute we were able to restart the car. Took it back to the dealership and they were not able to get any codes or reason why it happened. Now 3 weeks later it happened again, and back at the same dealership from where I purchased it. Again, same story that they are not able to get any codes as to what malfunctioned.
NHTSA complaint #11537552 — an unverified report by a vehicle owner.
Yonkers, NY
WHEELS
This is [XXX], a Mercedes customer who purchased a brand new 2023 GLS 450 (VIN:[XXX] ) in April 2023 from the Mercedes dealer in White Plains NY. I am contacting you about the Mercedes rusting claim. On May 22, 2023, less than a month after the purchase, a sheer of orange powdery rust was discovered (video available) on all steel frames of the four wheels. I contacted the sales person ([XXX]) , who referred to a manager ([XXX]) who told me that it was “normal because every car in our parking lot has the same thing.” I was very unhappy and disappointed with the response. The rusting obviously is a defect which is not normal. It is potentially dangerous and deadly for customers. INFORMATION Redacted PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6).
NHTSA complaint #11523840 — an unverified report by a vehicle owner.
Yonkers, NY
UNKNOWN OR OTHER
This is [XXX], a Mercedes customer who purchased a brand new 2023 GLS 450 (VIN:[XXX] ) in April 2023 from the Mercedes dealer in White Plains NY. I am contacting you about the Mercedes rusting claim. On May 22, 2023, less than a month after the purchase, a sheer of orange powdery rust was discovered (video available) on all steel frames of the four wheels. I contacted the sales person ([XXX]) , who referred to a manager ([XXX]) who told me that it was “normal because every car in our parking lot has the same thing.” I was very unhappy and disappointed with the response. The rusting obviously is a defect which is not normal. It is potentially dangerous and deadly for customers. INFORMATION Redacted PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6).
NHTSA complaint #11523840 — an unverified report by a vehicle owner.
Yonkers, NY
SERVICE BRAKES
This is [XXX], a Mercedes customer who purchased a brand new 2023 GLS 450 (VIN:[XXX] ) in April 2023 from the Mercedes dealer in White Plains NY. I am contacting you about the Mercedes rusting claim. On May 22, 2023, less than a month after the purchase, a sheer of orange powdery rust was discovered (video available) on all steel frames of the four wheels. I contacted the sales person ([XXX]) , who referred to a manager ([XXX]) who told me that it was “normal because every car in our parking lot has the same thing.” I was very unhappy and disappointed with the response. The rusting obviously is a defect which is not normal. It is potentially dangerous and deadly for customers. INFORMATION Redacted PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6).
NHTSA complaint #11523840 — an unverified report by a vehicle owner.