Mercedes-Benz SLK R172
Weaknesses, engine ratings and buying advice
421 PS
5.5L V8 NA AMG Benzin
Last of Its Kind — NA V8 in a Compact Roadster
Legendary!120–204 PS
2.1L Diesel Diesel
6 weaknesses
Stay Away!Generations
Engine Overview
The Mercedes-Benz SLK R172 is available with 5 engine variants — from 120 to 435 hp. 1 variants had engine changes — the model year is crucial.
The Mercedes-Benz SLK 250 CDI (Diesel, 204 PS) has the OM651DE22 (2.1L Diesel) — rated: "Stay Away!", 6 known weaknesses.
The Mercedes-Benz SLK 200 (Benziner, 184 PS) comes with 2 different engines: M271 (2011–2015, Stay Away!) und M274 (2015–2016, Be Careful). Pay attention to the model year for the SLK 200!
The Mercedes-Benz SLK 250 (Benziner, 204 PS) has the M271 (1.8L Kompressor) — rated: "Stay Away!", 6 known weaknesses.
The Mercedes-Benz SLK 350 (Benziner, 306 PS) has the M276 (3.0-3.5L V6) — rated: "Be Careful", 10 known weaknesses.
The Mercedes-Benz SLK 55 AMG (Benziner, 421 PS) has the M152 (5.5L V8 NA AMG) — rated: "Be Careful", 7 known weaknesses.
Vehicle Weaknesses
| Weakness | Cost | |
|---|---|---|
| Vario roof leaking -- water enters interior On the SLK R172, water penetrates through the seal of the folding metal roof in heavy rain, particularly on early production years up to approximately 2013. The seals in the area of the top left roof rail are most affected. Symptoms: Damp vehicle interior after rain, water stains on interior trim, musty smell in cockpit from 50,000 km | High | |
| Polycarbonate roof panel cracks and leaks Early SLK R172 models up to approximately 2013 were delivered with a polycarbonate roof panel (panoramic roof) prone to cracking and leaks. The glass roof (standard from 2013) is considered significantly more robust. Symptoms: Visible cracks in roof panel, water ingress into cockpit, sounds of leaks while driving from 60,000 km | High | |
| Magic Sky film or panoramic roof delaminates The film of the optional Magic Sky Control panoramic roof detaches from the carrier material and is visible from outside. Mercedes classified this as a visual defect. Early polycarbonate roofs (up to mid-2012) are also prone to cracking. Symptoms: Visible bubbles or detachment of roof film from outside, cloudy or discoloured areas in panoramic roof | High |
Top Reported Issues
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Known Problems and Issues
A total of 41 weaknesses have been documented for the Mercedes-Benz SLK R172 (2011–2016) — 35 engine-related and 6 vehicle-related. 2 problem engines: OM651DE22 (2.1L Diesel), M271 (1.8L Kompressor). Typical issues affect Body, Suspension, Interior, Electronics.
SLK (OM651DE22, 2012–2015) — Stay Away!: Chain Tensioner Seal Leaking — Recall, Timing Chain Stretch (Simplex Chain), Piezo Injector Faults. Power: 204 PS.
SLK (M271, 2011–2015) — Stay Away!: Timing Chain Stretches Prematurely, Camshaft Adjuster Leaks — Oil in Wiring Harness, Camshaft Adjuster Leaks Oil into Connector. Power: 184 PS.
SLK (M271, 2011–2015) — Stay Away!: Timing Chain Stretches Prematurely, Camshaft Adjuster Leaks — Oil in Wiring Harness, Camshaft Adjuster Leaks Oil into Connector. Power: 204 PS.
SLK (M276, 2011–2015) — Be Careful: Oil cooler leaking in the V-block, Camshaft adjuster leaking — wiring harness contaminated, Piston slap (early 3.5L variants). Power: 306 PS.
SLK (M152, 2012–2015) — Be Careful: Silitec Cylinder Liner Wear-Prone — Total Damage Possible, Faulty Injectors — Cylinder Bore Destruction, Timing Chain Requires Preventive Replacement at 150,000 km. Power: 421 PS.
SLK (M274, 2015–2016) — Be Careful: High-Pressure Pump Faulty or Noisy, Camshaft Adjuster Leaks — Oil in Wiring Harness, Electric thermostat failure. Power: 184 PS.
What to watch out for with the Mercedes-Benz SLK? See the detailed listing of all engine and vehicle weaknesses in the sections above.
Frequently Asked Questions
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Last updated: February 2026 · All information without guarantee