The Lemon Index
Mercedes-AMG's 2.0 L turbo, mild hybrid inline-4 in the Mercedes-Benz AMG GT 43 (coupe), model years 2025.
A safer bet: YouTube owner tone 53/100, #46 of 165 engines with a YouTube study (in the top third); no engine-related recall on record, 1 known issue listed below.
Reliability by year
Not enough complaints to chart. We found no government complaints we can tie to this engine's cars. Supercars sell in small numbers, so we show YouTube, recalls and the automaker's repair notes instead.
Why the car page shows more: the C63 page counts 0 complaints and 0 recall campaigns for 2024–2025, everything NHTSA files as "Amg C63", other engines included. This page counts only the 0 complaints and 0 recalls we can tie to the Mercedes-AMG M139 by model name or the owner's own words.
How we count: owner complaints only where the car's name and year leave no doubt; YouTube tone from videos that name this engine or its cars. How we count
Owner complaints (NHTSA) are filed by model and year, not engine. We count one for this engine only when the model name and year had no other engine (e.g. "488 GTB", "GT-R"), or when the owner's own words name a version that had only this engine that year (Z06, ZR1, Hellcat, GT500 ...). They cover the whole car (wheels, air bags, electrics ...), not only the engine, and none of them is a failure rate. We chart them only for engines with 30 or more, over 3 or more years. YouTube tone = how positive the videos are, 0–100, from titles and transcripts (praise vs trouble words, the title counts 3 times), weighted by views; a year needs at least 3 videos' worth. A video counts for this engine when its title names the engine or a car that only had this engine in the years it names; a video whose title names no model year counts toward every year of that car, so neighboring years share most of their videos.
All the numbers, year by year
| Year | Cars | Owner complaints | YouTube says | Recalls |
|---|---|---|---|---|
| 2025 | Mercedes-Benz AMG GT 43 (coupe) | 0 | 53 (39 videos) | 0 |
Recalls on cars with this engine
No NHTSA recalls we can tie to this engine's cars.
Known issues on record
- Broken valve springs (Maker bulletin). A Mercedes bulletin for all M139 engines covers broken valve springs: check-engine light, rough running and trouble starting. Fix: Dealers run a compression test and replace the broken springs and any damaged parts.
Sources: Mercedes-Benz bulletin LI01.30-P-075439: M139 engine, broken valve springs (Nov 2025, filed with NHTSA). The same list as on the C63 page.
Every US version with this engine
| Car and versions | Years |
|---|---|
| Mercedes-AMG GT AMG GT 43 (coupe) | 2025 |
Engine code: M139. Hand-assembled, one engine per builder. Power: 416 hp, factory figures. Versions and years: EPA (fueleconomy.gov). Sources: Mercedes-Benz M139 engine · Mercedes-AMG GT.
Quick answers
What cars have the Mercedes-AMG M139 engine?
In the US: the Mercedes-Benz AMG GT 43 (coupe), model years 2025–2025. See the version table for each one.
Is the Mercedes-AMG M139 reliable?
Mostly yes. YouTube owner tone 53/100, #46 of 165 engines with a YouTube study (in the top third); no engine-related recall on record, 1 known issue listed below. Not enough owner complaints to judge it per car: supercars sell in small numbers. Have any used car inspected.
How much horsepower does the Mercedes-AMG M139 make?
416 hp in factory figures, depending on the car.