2020 Mercedes-Benz Gls450 Problems, Recalls & Reliability
Verdict
AvoidComplaint Index
100/100
#1 most-complained of 6 Gls450 years
Based on NHTSA complaints per model-year, not a reliability rating. Methodology
The 2020 Mercedes-Benz Gls450 ranks worst among its 6 model years, with a Complaint Index of 100 and 36 complaints tied to 22 recalls. Electrical System issues drive half of all complaints, with a median failure mileage of 6,550 miles, making 2020 the year to avoid.
- Complaints
- 36
- Recalls
- 22
- Crashes / fires
- 3 / 1
- Injuries / deaths
- 3 / 0
- NHTSA overall rating
- Not rated
- EPA combined MPG
- 21
- 19 city / 23 hwy
Top 2020 Mercedes-Benz Gls450 problems
NHTSA owner complaints by component group. Groups with 15+ complaints have their own page.
- Electrical System18 (50%)
- Engine10 (28%)
- Collision Avoidance & Cameras7 (19%)
- Fuel System7 (19%)
- Other4 (11%)
- Transmission & Powertrain4 (11%)
- Structure & Body3 (8%)
- Airbags2 (6%)
- Brakes2 (6%)
- Visibility & Wipers2 (6%)
What owners report
- Owners report sudden loss of power and engine shutdown while driving at 25-30 mph, tied to 48V electrical system warnings.
- The 48V battery malfunction warning has triggered an instruction not to drive, with acceleration lost mid-drive on a highway.
- The engine reportedly dies when slowing down or turning and will not restart until the vehicle is fully powered off and back on.
- A backup camera and gear shifter reportedly locked in reverse during a low-speed reversing maneuver, disabling the brake pedal and emergency brake.
- Owners describe a fuel odor entering the cabin through open windows, in one case severe enough to require medical attention.
- Engine wiring harness insulation near ignition coil connectors reportedly deteriorated from heat exposure, causing misfires and ignition circuit faults.
2020 Mercedes-Benz Gls450 recalls
22 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 23V177000Mar 17, 2023HVAC61,450 vehicles
Visibility:defroster/defogger/HVAC system
Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2020-2021 GLE350, GLE450, GLS450, GLS580, 2021 AMG GLE53, AMG GLE63, Maybach GLS600, AMG GLS63, and 2020 GLE580 vehicles. The air conditioner drain hoses may have been incorrectly installed, causing water to drain into the passenger compartment.
Risk: Water intrusion into the foot wells may cause corrosion and/or short circuits to electrical components, increasing the risk of fire. In addition, the emergency call (eCall) feature may be disabled and the doors may not unlock, increasing the risk of injury. Also, the engine may not start or may enter a limp-home mode, increasing the risk of a crash.
Remedy: Dealers will inspect and reinstall the air conditioner drain hoses, as necessary, free of charge. Owner notification letters were mailed April 28, 2023. Owners may contact MBUSA customer service at 1-800-367-6372. This recall is an expansion of recall numbers 21V-288 and 19V-587. MBUSA's numbers for this recall are 2023030014 and 15.
2020 Mercedes-Benz Gls450 fuel economy and fuel cost
- City
- 19 MPG
- Highway
- 23 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.
2020 compared with other Gls450 years
Frequently asked questions
- Is the 2020 Mercedes-Benz Gls450 reliable?
- Based on NHTSA owner complaints and recalls, the 2020 Gls450 ranks worst of the 6 model years with data, carrying a Complaint Index of 100 and 22 recalls.
- What is the biggest problem with the 2020 Mercedes-Benz Gls450?
- The Electrical System is the top problem area, accounting for 18 of 36 complaints (50%), with a median failure mileage of 6,550 miles and one reported fire.
- Does the 2020 Mercedes-Benz Gls450 have a transmission recall?
- Yes. NHTSA recall 24V118000 covers 2020-2023 GLE 450 and GLS 450 vehicles for a transmission that may not fully downshift, causing the engine to stall.
- How does the 2020 Gls450 compare to other years?
- The 2020 Gls450 has a Complaint Index of 100, the highest of the years listed, compared to 20 for 2018 and 40 for 2019, both rated better by comparison.
- Are there airbag issues on the 2020 Mercedes-Benz Gls450?
- Yes. Recall 22V466000 covers 2020 GLS 450 and GLS 580 vehicles where the front air bag wiring harness may be routed incorrectly, preventing proper deployment.