2021 Mercedes-Benz Gls450 Problems, Recalls & Reliability
Verdict
AvoidComplaint Index
80/100
#2 most-complained of 6 Gls450 years
Based on NHTSA complaints per model-year, not a reliability rating. Methodology
The 2021 Mercedes-Benz Gls450 ranks 2nd worst out of 6 model years, with a Complaint Index of 80 and 30 complaints tied to 12 recalls. Electrical System issues, mostly 48-volt battery failures, dominate at 47% of complaints, some causing stalls and two fires.
- Complaints
- 30
- Recalls
- 12
- Crashes / fires
- 1 / 2
- Injuries / deaths
- 1 / 0
- NHTSA overall rating
- Not rated
- EPA combined MPG
- 21
- 20 city / 24 hwy
Top 2021 Mercedes-Benz Gls450 problems
NHTSA owner complaints by component group. Groups with 15+ complaints have their own page.
- Electrical System14 (47%)
- Other8 (27%)
- Engine4 (13%)
- Lane Departure3 (10%)
- Structure & Body3 (10%)
- Collision Avoidance & Cameras2 (7%)
- Suspension, Wheels & Tires2 (7%)
- Fuel System1 (3%)
- Seat Belts1 (3%)
- Transmission & Powertrain1 (3%)
What owners report
- Owners report the 48-volt battery system failing and shutting the vehicle off while driving, including at highway speed in traffic.
- The dashboard shows warnings such as "48-volt battery failure" and "check engine" before the vehicle loses power and later restarts on its own.
- Some vehicles would not start on multiple separate occasions and required towing to a dealer for 48-volt battery replacement.
- Adaptive cruise control has been reported to unexpectedly decelerate the vehicle from highway speed down to as low as 15 mph with no warning light.
- The Lane Departure system has independently jerked the steering while attempting to avoid a pedestrian or object, and separately caused repeated stalling that nearly led to a crash.
- One owner reported smoke and fire coming from under the passenger seat, resulting in a total loss of the vehicle.
2021 Mercedes-Benz Gls450 recalls
12 NHTSA recall campaigns list this model year.
- NHTSA 24V207000Mar 15, 2024Electrical System116,020 vehicles
Electrical system:wiring
Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2023-2024 GLE 350, 2020-2024 GLE 450, 2020-2023 GLS 580, GLE 580, 2019-2023 GLS 450, 2021-2023 Maybach GLS 600, AMG GLS 63, 2021-2024 AMG GLE 53, AMG GLE 53 Coupe, and AMG GLE 63 S vehicles. A 48-Volt ground connection under the passenger seat may not be secured properly, resulting in the ground connection overheating.
Risk: An overheated ground connection can increase the risk of a fire.
Remedy: Dealers will inspect and tighten the 48-Volt ground connection as necessary, free of charge. Owner notification letters were mailed on May 3, 2024. Owners may contact MBUSA customer service at 1-800-367-6372. MBUSA's number for this recall is 2024040002.
- NHTSA 24V118000Feb 16, 2024Transmission & Powertrain105,071 vehicles
Power train:automatic transmission:control module:software
Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2020-2023 GLE 450 and GLS 450 vehicles. The transmission may not fully downshift in certain conditions, causing the engine to stall.
Risk: An engine stall increases the risk of a crash.
Remedy: Dealers will update the transmission control unit software, free of charge. Owner notification letters were mailed March 29, 2024. Owners may contact MBUSA customer service at 1-800-367-6372.
- NHTSA 23V445000Jun 26, 2023Fuel System143,551 vehicles
Fuel system, gasoline:delivery:fuel pump
Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2021-2023 C-Class, E-Class, S-Class, CLS, SL, GT, GLC, GLE, GLS, and G-Class vehicles. Please refer to MBUSA's recall report for specific vehicle details. The fuel pump may shutdown, which can result in a loss of drive power.
Risk: A loss of drive power can increase the risk of a crash.
Remedy: Dealers will replace the fuel pump, free of charge. Owner notification letters were mailed on June 14, 2024. Owners may contact MBUSA customer service at 1-800-367-6372. MBUSA's number for this recall is 2023070012.
2021 Mercedes-Benz Gls450 fuel economy and fuel cost
- City
- 20 MPG
- Highway
- 24 MPG
- Combined
- 21 MPG
- Annual fuel cost (EPA)
- $3,800
- 15,000 mi/yr
- Fuel
- Premium
- Current regular gas
- $4.32/gal
- national avg.
EPA figures; median across configurations of this model year. Estimate your own cost with the fuel cost calculator.
2021 compared with other Gls450 years
Frequently asked questions
- Is the 2021 Mercedes-Benz Gls450 reliable?
- Based on NHTSA owner complaints and recalls, the 2021 model ranks 2nd worst of 6 model years with a Complaint Index of 80 and 12 recalls, giving it an Avoid verdict relative to other Gls450 years.
- What is the biggest problem with the 2021 Gls450?
- The Electrical System is the top problem area, accounting for 47% of complaints (14 of 30), largely tied to 48-volt battery failures reported at a median mileage of 11,000 miles.
- Does the 2021 Gls450 have recalls?
- Yes, NHTSA lists 12 recalls for the 2021 Gls450, covering the Electrical System, Transmission & Powertrain, Fuel System, HVAC, and Structure & Body, none of which are do-not-drive recalls.
- How does the 2021 Gls450 compare to other years?
- The 2021 model (Complaint Index 80) is worse than 2018 (20, Best), 2019 (40, Good), and 2017 (60, Caution), but slightly better than 2020 (100, Avoid).
- Were there any fires reported in the 2021 Gls450?
- NHTSA data shows 2 fire incidents for the 2021 model year, both linked to the Electrical System, with one injury reported and no deaths.