GarageCalc What the data says
Forward collision avoidance: automatic emergency braking accounts for about 33% of this year's Mercedes-Benz GLS 450 4MATIC complaints. That is a moderate concentration; worth knowing, but complaints are spread across several areas.
The 2024 model year contributes 7 complaints (47%). No single model year dominates, so this looks like a line-wide pattern rather than one bad year.
Not enough 2025 complaints to compute a year-over-year trend (6 in the same window last year). Year-over-year movement is the most useful signal here: a model's sales are roughly stable from one year to the next, so a sharp rise means the per-vehicle complaint rate genuinely moved, not just that the model is popular.
How to read this
Raw complaint totals track how many Mercedes-Benz GLS 450 4MATICs are on the road as much as they track quality, so a high count on a best-seller is partly a volume story. Complaints are also self-reported: they capture what owners chose to file, not a controlled survey. Use these numbers to know where to look during a pre-purchase inspection and which recalls to check, not as a verdict on their own. Compare any car instantly in the Car Complaint Checker, or read the full 2026 study for the market-wide picture and methodology.
Frequently asked questions
Is the Mercedes-Benz GLS 450 4MATIC reliable?
Complaint counts alone cannot answer that, because they track how many are on the road as much as build quality. What the 2026 data shows: 15 NHTSA complaints so far (rank 314 of 765 models), too few 2025 complaints for a trend, with forward collision avoidance: automatic emergency braking the most-cited area. Treat it as a starting point and cross-check recalls and a pre-purchase inspection for the specific vehicle.
What is the most common Mercedes-Benz GLS 450 4MATIC complaint?
Forward collision avoidance: automatic emergency braking: 5 of the 15 complaints filed in 2026 cite it (about 33%). That is a moderate concentration; worth knowing, but complaints are spread across several areas.
Which Mercedes-Benz GLS 450 4MATIC model year has the most complaints?
The 2024 model year, with 7 of this year's 15 complaints (about 47%). No single model year dominates, so this looks like a line-wide pattern rather than one bad year.
Source: NHTSA Office of Defects Investigation complaint database, complaints received 2026-01-01..2026-08-24, compared with 2025-01-01..2025-08-24 (same window). Counted once per complaint ID, vehicles only. Aggregated data is available under CC BY 4.0 with a link to GarageCalc.