2021 Mercedes-Benz GLS 450 Vehicle speed control Problems
- Complaints
- 1about this part
- Share
- 3%of 31 total for the year
- Median mileage
- 3,000miles
- Trend
- Not enough dataFewer than 15 complaints, too few for a reliable trend.
NHTSA recorded 1 complaints about the vehicle speed control of the 2021 Mercedes-Benz GLS 450, 3% of the 31 complaints for this model year. Where a mileage was given, the median is 3,000 miles.
Fewer than 15 complaints name this part, so treat the figures as a rough indication only.
Example complaints
Selected from NHTSA records; personal details are removed. They are consumer reports, not findings.
“The contact owns a 2021 Mercedes Benz GLS450. The contact stated while driving 75 mph with the cruise control engaged, the vehicle decelerated to 45 mph than to 15 mph. On another occasion, while driving 80 mph, the vehicle independently decelerated to 45 mph. There was no warning light illuminated. The vehicle was taken to the local dealer however, the mechanic was unable to duplicate the failure. The vehicle was not diagnosed nor repaired. The contact stated that the cruise control and speed assistance feature provided erroneous information. The manufacturer was notified of the failure. …”
NHTSA complaint #11426426, filed 2021-07, 3,000 milesVehicle speed control: other model years
Other parts of the 2021 Mercedes-Benz GLS 450
14 complaintsOther or unknown
8 complaintsEngine
3 complaintsLane departure
3 complaintsForward collision avoidance
2 complaintsSeats
2 complaintsFuel system
1 complaintsSeat belts
1 complaintsSteering
1 complaintsBody and structure
1 complaintsTires
1 complaintsTransmission and drivetrain
1 complaints
← All problems reported for the 2021 Mercedes-Benz GLS 450
About this data. Data from NHTSA (ODI) complaints, recalls, TSBs and investigations, updated Oct 31, 2026. Complaints are unverified consumer reports and may be duplicated or inaccurate.
To check a specific vehicle for open recalls, use its VIN at nhtsa.gov/recalls. Methodology