2021 Mercedes-Benz Gls-Class
Vehicle Specs & Maintenance Data
The 2021 Mercedes-Benz Gls-Class maintenance specs on this page cover the key fluids, torque values, and wear items you need for routine service. Use these numbers as a quick reference when performing oil changes, tire rotations, brake jobs, and other scheduled maintenance on your Mercedes-Benz Gls-Class.
For oil changes, the 2021 Mercedes-Benz Gls-Class takes 0W-40 Full Synthetic motor oil with a capacity of 8.5 quarts. Brake fluid type is DOT 4, the recommended coolant is MB 325.0 (Blue, silicate-free), and transmission fluid is MB 236.14. Always use the manufacturer-recommended fluids to maintain warranty coverage and engine longevity.
When mounting wheels on the Mercedes-Benz Gls-Class, torque the lug nuts to 96 ft-lbs using a calibrated torque wrench. Over- or under-torquing can lead to warped brake rotors or loose wheels. Re-torque after 50 to 100 miles on newly installed wheels.
Owners of the 2021 Mercedes-Benz Gls-Class have reported 5 common issues including "AIRMATIC Air Suspension Failure", "MBUX Infotainment Glitches" and "Third-Row Seat Motor Failure". Scroll down to the Diagnostics tab for detailed descriptions, solutions, and estimated repair costs.
Specifications on this page are compiled from multiple publicly available sources including manufacturer documentation, NHTSA data, and automotive databases. Always cross-reference with your owner's manual or official factory documentation before purchasing parts or performing any service.
The 2021 Mercedes-Benz Gls-Class uses 0W-40 Full Synthetic motor oil (8.5 qt capacity), requires lug nuts torqued to 96 ft-lbs, takes DOT 4 brake fluid.
Manufacturer-recommended maintenance schedule for the 2021 Mercedes-Benz Gls-Class. Always verify intervals against your owner's manual.
Enter a diagnostic trouble code to see causes, symptoms, and fixes for the 2021 Mercedes-Benz Gls-Class.
Common problems reported by 2021 Mercedes-Benz Gls-Class owners, with recommended fixes and estimated repair costs.
AIRMATIC Air Suspension Failure
The AIRMATIC air suspension struts develop leaks, causing the vehicle to sag on one or more corners overnight. The air compressor overworks trying to maintain ride height and can burn out. Common after 50,000-60,000 miles.
Replace the failed air struts and/or compressor. OEM struts are expensive; Arnott and other aftermarket suppliers offer alternatives at lower cost. The air dryer should be replaced simultaneously to prevent moisture damage to new struts.
Est. Cost: $1,500 - $3,500 per strutMBUX Infotainment Glitches
The MBUX system experiences crashes, lag, voice assistant failures, and loss of Apple CarPlay/Android Auto connectivity. The augmented reality navigation overlay can malfunction, showing incorrect directional arrows.
Dealer applies software updates. System resets resolve many intermittent issues. The MBUX head unit may require replacement for persistent hardware faults. Mercedes has released multiple OTA updates for the GLS.
Est. Cost: $0 (software update) - $3,000 (head unit)Third-Row Seat Motor Failure
The power-folding third-row seat mechanism develops motor failures, preventing the seats from folding flat or returning to the upright position. The seat may get stuck in an intermediate position, blocking cargo access.
Replace the third-row seat motor and linkage assembly. A manual override cable can fold the seats in an emergency. Check for wiring harness chafing under the seats that can cause intermittent faults.
Est. Cost: $600 - $1,500E-ACTIVE BODY CONTROL Hydraulic Leaks
Vehicles equipped with the optional E-ACTIVE BODY CONTROL system develop hydraulic fluid leaks from the active suspension struts and lines. Warning lights appear and the system defaults to a stiff, uncomfortable ride.
Replace the leaking hydraulic struts and/or hydraulic lines. The E-ACTIVE system is significantly more expensive to repair than the standard AIRMATIC. Some owners convert to the base AIRMATIC system to reduce complexity.
Est. Cost: $3,000 - $8,000Windshield Wiper System Malfunction
The rain-sensing wiper system activates erratically or fails to respond. The wiper motors may operate at incorrect speeds. The large panoramic windshield option is particularly susceptible to sensor calibration issues.
Recalibrate the rain sensor and replace if faulty. Check wiper motor connections and replace the motor if speed control is erratic. Software update to the body control module may resolve sensor calibration issues.
Est. Cost: $200 - $800