The 2021 Metris with the M274 2.0L turbo is a Euro-commercial van that suffers from serious engine longevity issues and transmission cooling failures, often requiring catastrophic repairs well before 100,000 miles. Not the reliable workhorse many buyers expect from a Mercedes badge.
Catastrophic Engine Failure - Connecting Rod/Bearing Failure
Occasional · high severityTypical onset: 60,000-90,000 mi
Symptoms: Sudden knocking or ticking noise from lower engine, Metal shavings in oil during change, Loss of oil pressure warning, Complete engine seizure in worst cases
Fix: M274 engine has known issues with connecting rod bearings failing prematurely, especially in commercial/heavy-use scenarios. Fix requires complete engine rebuild or short-block replacement. Expect 18-25 labor hours for rebuild, 12-16 for short block swap. Many shops recommend outright replacement over rebuild due to repeat failures.
Estimated cost: $8,000-$14,000
Transmission Oil Cooler Failure
Common · high severityTypical onset: 50,000-80,000 mi
Symptoms: Transmission fluid mixing with coolant (strawberry milkshake in reservoir), Transmission slipping or harsh shifts, Overheating warnings, Pink or brown residue in coolant overflow tank
Fix: Internal cooler in radiator fails, allowing cross-contamination between ATF and coolant. Requires radiator replacement, complete transmission fluid flush (often multiple cycles), and sometimes transmission rebuild if contamination went undetected. 6-8 hours labor for cooler/flush, add 15-20 if transmission damaged.
Estimated cost: $1,800-$3,200 (cooler/flush only), $5,500-$8,500 (if trans rebuild needed)
Transmission Mount Collapse
Common · medium severityTypical onset: 40,000-70,000 mi
Symptoms: Severe clunking when shifting from Park to Drive, Vibration at idle in gear, Visible sagging of transmission when inspected from below, Rough engagement during acceleration
Fix: Hydraulic transmission mount fails prematurely, especially in cargo-heavy applications. Replacement is straightforward but requires supporting drivetrain. 2.5-3.5 hours labor. Use OE Mercedes part - aftermarket mounts fail even faster.
Estimated cost: $650-$950
Fuel Filter/Fuel Pump Clogging and Failure
Occasional · medium severityTypical onset: 50,000-80,000 mi
Symptoms: Hard starting, especially when warm, Loss of power under load, Rough idle or stumbling, Check engine light with fuel pressure codes (P0087, P0191)
Fix: Fuel filter clogs earlier than expected (Mercedes spec says lifetime, reality is 50-60k). Restricted filter kills the pump. Filter alone is 1.5 hours, pump replacement adds another 3-4 hours if tank must drop. Some techs access pump through rear seat area to save time (2 hours). ALWAYS replace filter when doing pump.
Estimated cost: $450-$750 (filter only), $1,200-$1,800 (pump + filter)
Brake Fluid Contamination from ABS Module
Occasional · medium severitySymptoms: Spongy brake pedal, ABS/ESP warning lights, Brownish or black brake fluid on inspection, Reduced braking performance
Fix: Internal seals in ABS/ESP module degrade and contaminate brake fluid. Requires complete system flush and ABS module replacement. Some cases covered under recall/service campaign if caught early. 4-5 hours labor for module replacement and complete bleed.
Estimated cost: $1,800-$2,800
Head Gasket Failure (Both Banks)
Rare · high severityTypical onset: 70,000-110,000 mi
Symptoms: White smoke from exhaust, Coolant loss with no visible leak, Overheating episodes, Oil contamination in coolant or vice versa, Misfires on cold start
Fix: M274 occasionally blows head gaskets, sometimes related to cooling system neglect or overheating from trans cooler failure. Both heads typically done together. 14-18 hours labor, includes machining if heads are warped. If caught late, cylinder damage may require full rebuild.
Estimated cost: $4,500-$6,500 (gaskets only), $8,000+ (if bore damage present)
Hard pass unless you find one with documented engine replacement under warranty and verified transmission cooler update - the M274's catastrophic failure rate makes this a gamble even at low mileage.
AI-assisted summary drawn from NHTSA recall data, our labor-times database, and platform knowledge. Not a substitute for a pre-purchase inspection on a specific vehicle.