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Mercedes-Benz GLS 450Model year report

2020 Mercedes-Benz GLS 450 Problems

Compared with other Mercedes-Benz GLS 450 years

Typical for this model

50/100 1.0× a typical year · 50 = typical

Nearby years with a typical complaint level and no open NHTSA investigation: 2017

Based only on NHTSA complaints, recalls and investigations. Not adjusted for how many vehicles were sold, and not a reliability rating. How this is calculated

Complaints
36filed with NHTSA
Median mileage
4,200miles, 5 complaints with mileage
Recalls
22campaigns on record
Trend
RisingComplaints filed in the last 3 full calendar years are at least 25% higher than in the 3 years before.
NHTSA crash rating
—no overall rating published
EPA fuel economy
21 mpgcombined, 3.0L 6-cyl · hybrid 4WD · 19 city / 23 hwy

Sources: NHTSA records for the 2020 Mercedes-Benz GLS 450 (complaints, recalls, investigations), EPA fuel economy. Report an error

NHTSA recorded 36 consumer complaints for the 2020 Mercedes-Benz GLS 450. The part named most often is electrical system, with 18 complaints (50% of the total), followed by engine (9) and forward collision avoidance (7). 5 of the complaints include a mileage, and 80% of those were filed for vehicles with under 50,000 miles; the median is 4,200 miles. Of all complaints, 3 involved a crash, 1 a fire, 3 an injury, according to the filers. NHTSA lists 22 recall campaigns and 270 technical service bulletins for this model year. Electrical system complaints overlap with 5 recall campaigns covering the interior/under dash and 128 technical service bulletins filed under the same part. Engine complaints overlap with 10 technical service bulletins filed under the same part. Compared with the other 2 Mercedes-Benz GLS 450 model years that have at least 25 complaints and are old enough to compare, this one scores 50 out of 100, where 50 is a typical year for the model (typical for this model). The comparison allows for the era and for how long each year has had to collect complaints, but not for how many vehicles were sold.

Which parts are reported most

Complaints can name more than one part, so the counts add up to more than the total. Select a part to see its complaints, recalls and bulletins.

Also reported: Visibility (wipers, defrost, mirrors) (2), Seats (1), Steering (1), Suspension (1), Vehicle speed control (1).

Example complaints

Electrical system: “We purchased a new 2020 mercedes benz gls 450 in october 2019 from the oakland dealership and shipped the car to hawaii. The vehicle is now 117 months old and has about 4100 miles. Because our vehicle is lightly used we arranged for mercedes benz to supply and installed a 'battery minder' to keep the vehicles 48 volt system charged when we are away for an extended time. However we did not have the battery minder hooked up at this time because we are using the vehicle on a weekly basis. …”

NHTSA complaint #11402929, filed 2021-03, 4,200 miles

Engine: “On numerous occasions, when either slowing down or in a slow turn, the engine dies and will not reengage until I have turned off the vehicle, exited, then reentered an started the vehicle. I have had passengers in the vehicle who will attest to this occurring, in fact, the last time it happened, I was almost broadsided when the vehicle stopped in the middle of a left-hand turn, crossing three lanes of oncoming traffic. The vehicle has been to the dealership at least three times and it's either a software update requirement or we can't duplicate the issue. …”

NHTSA complaint #11465253, filed 2022-05

Forward collision avoidance: “On a sunny afternoon without zero clouds in the sky, 75 degrees I was driving at 35 mph on a two-lane road with no cars in front of me, behind me, or coming in the other direction, the brakes were urgently and automatically applied and the seat belts dramatically tightened. The system showed a large red X on the screen. It was obvious the automated safety system mistakenly thought we were about to crash into something but there wasn't anything but smooth asphalt.”

NHTSA complaint #11726166, filed 2026-03

Fuel system: “While driving, vehicle has abruptly stopped/engine turned off causing car to not accelerate and come to a stop. One instance was on a busy freeway, causing our family to pull off the interstate with nearly no curb, risking rear-end collision due to the abrupt stalling of the vehicle. In this instance, the 48 volt battery failure warning, engine overheat warning, engine light warning came on. When MCB dealership evaluated the vehicle, there were no stored associated error codes and MCB service returned the vehicle to me saying that the issue did not occur when they drove it. …”

NHTSA complaint #11464919, filed 2022-05

Mileage when problems were reported

80% of the 5 complaints with a mileage were filed for vehicles with under 50,000 miles; the middle half falls between 1,000 and 8,900 miles.

80%0–100%10–250%25–5020%50–750%75–1000%100–1500%150+
Share of complaints by mileage when the problem was reported, in thousands of miles (5 complaints with mileage). Red bars: under 50,000 miles. Bucket widths differ. Median: 4,200 miles.

Complaints by year filed

Trend: rising. Complaints filed in the last 3 full calendar years are at least 25% higher than in the 3 years before.

20202021202220232024820252026
Complaints by year the complaint was filed with NHTSA. Red bars: the last 3 full calendar years used for the trend. The current year (2026) is partial.

Fuel economy and running cost

EPA ratings for each 2020 Mercedes-Benz GLS 450 version. Annual fuel cost is the EPA's estimate at its current fuel prices for 15,000 miles a year (55% city driving).

VersionEngineTransmissionCityHwyComb.Fuel / yr
GLS450 4matic 4WD3.0L 6-cyl · hybrid9-speed automatic192321$3,900

Source: U.S. EPA and Department of Energy, fueleconomy.gov. Ratings are for comparing vehicles; real-world mileage varies with driving and conditions.

Recalls and investigations

See all 22 recalls for the 2020 Mercedes-Benz GLS 450 → · Check a VIN at nhtsa.gov/recalls

Technical service bulletins

TSBs are manufacturer notes to dealers about known repair procedures. They are not recalls and do not by themselves mean a vehicle has a fault. 270 on record; the latest 10 are shown.

See all 270 bulletins →

Other model years of the Mercedes-Benz GLS 450

YearComplaintsMedian miRecallsCrash ★MPGScore (50 = typical)Trend
20213111,00012—2154 · TypicalRising
2020364,20022—2150 · TypicalRising
20192431,4153—18—Rising
2018148,0003—19—Not enough data
20173513,0008—1943 · TypicalRising

All Mercedes-Benz GLS 450 model years · Best and worst years by complaints

Frequently asked questions

How many NHTSA complaints does the 2020 Mercedes-Benz GLS 450 have?

NHTSA recorded 36 consumer complaints for the 2020 Mercedes-Benz GLS 450 as of Oct 27, 2026. Complaints are unverified consumer reports and may be duplicated or inaccurate.

What part of the 2020 Mercedes-Benz GLS 450 is reported most often?

Electrical system is named most often, in 18 complaints (50% of the total), followed by engine with 9.

Has the 2020 Mercedes-Benz GLS 450 been recalled?

NHTSA lists 22 recall campaigns for this model year. To check a specific vehicle, enter its VIN at nhtsa.gov/recalls.

What gas mileage does the 2020 Mercedes-Benz GLS 450 get?

The EPA rates the 2020 Mercedes-Benz GLS 450 (GLS450 4matic, 3.0L 6-cyl · hybrid) at 21 mpg combined, 19 city and 23 highway, with an estimated annual fuel cost of $3,900 at 15,000 miles a year. Other engine and drive versions are rated differently.

At what mileage are problems with the 2020 Mercedes-Benz GLS 450 reported?

Among the 5 complaints that include a mileage, the median is 4,200 miles and the middle half falls between 1,000 and 8,900 miles; 80% were filed for vehicles with under 50,000 miles.

About this data. Data from NHTSA (ODI) complaints, recalls, TSBs and investigations, updated Oct 27, 2026. Complaints are unverified consumer reports and may be duplicated or inaccurate. Fuel economy is from the EPA and DOE (fueleconomy.gov).

Complaint counts come from NHTSA’s public complaint database; we count each complaint once. The source records for this vehicle are on nhtsa.gov. Scores and trends are our own summaries of that data, described in the methodology. This page is not legal, safety or repair advice: for a specific vehicle, check its VIN at nhtsa.gov/recalls and ask a qualified mechanic. See an error? Tell us.