The 2015 E63 AMG with the M157 5.5L BiTurbo is a high-strung performance machine that demands attention. When maintained religiously it's phenomenal, but deferred maintenance or aggressive use leads to catastrophic and expensive engine failures—particularly piston ring/bearing issues that plague many high-performance M157 units.
M157 Piston Ring Failure and Scoring
Occasional · high severityTypical onset: 60,000-100,000 mi
Symptoms: Excessive oil consumption (1+ quart per 1,000 miles), Blue smoke on cold start or hard acceleration, Loss of compression, rough idle, misfires, Metallic rattling from engine under load
Fix: Complete engine teardown required. Pistons, rings, cylinder honing at minimum; often leads to full short block replacement due to cylinder wall damage. 40-60 hours labor for proper rebuild or swap.
Estimated cost: $15,000-25,000
Rod and Main Bearing Wear (Oil Starvation)
Occasional · high severityTypical onset: 70,000-120,000 mi
Symptoms: Knocking or ticking noise at idle, especially when warm, Low oil pressure warning at operating temp, Sudden catastrophic failure if ignored—metal shavings in oil
Fix: Engine-out job. Requires crankshaft inspection, bearing replacement, often crank polishing or replacement if journals are scored. 35-50 hours labor; many techs opt for reman short block instead of piecemeal repair.
Estimated cost: $12,000-22,000
7-Speed MCT Transmission Oil Cooler Leaks
Common · medium severityTypical onset: 50,000-90,000 mi
Symptoms: Transmission fluid pooling under vehicle, Burnt ATF smell, low fluid level warnings, Harsh or delayed shifts when fluid runs low
Fix: Oil cooler lines or cooler itself corrode and leak. Front bumper removal required for proper access. Replace cooler, lines, and flush system. 4-6 hours labor.
Estimated cost: $1,200-2,200
Transmission Mounts Collapse
Common · medium severityTypical onset: 60,000-100,000 mi
Symptoms: Clunking when shifting from Park to Drive/Reverse, Vibration at idle in gear, Excessive driveline movement visible under throttle
Fix: Both front and rear transmission mounts commonly fail due to engine torque. Straightforward R&R but requires proper support of transmission. 3-4 hours labor.
Estimated cost: $800-1,400
Turbocharger Wastegate Rattle and Failure
Occasional · high severityTypical onset: 80,000-120,000 mi
Symptoms: Rattling from engine bay on cold start (wastegate flapper), Loss of boost pressure, limp mode, Check engine light with underboost codes (P0299, P003A)
Fix: Wastegate actuators seize or flapper arms break. Turbo replacement or rebuild required. Engine-out or subframe drop for access on some jobs. 12-18 hours labor per turbo.
Estimated cost: $4,000-7,000
Head Gasket Failure (Overheating or Neglect)
Rare · high severityTypical onset: 80,000-130,000 mi
Symptoms: Coolant loss with no visible leaks, White smoke from exhaust, Overheating, coolant in oil or oil in coolant, Rough idle, misfires on specific cylinders
Fix: Heads must come off, resurface, new gaskets, head bolts, timing components inspected. Often find additional damage if overheated. 25-35 hours labor.
Estimated cost: $8,000-14,000
Fuel Filter Clogging and Fuel System Contamination
Occasional · medium severitySymptoms: Hard starting, long cranking time, Hesitation or stumble under load, Limp mode if high-pressure pump is affected, Check engine light with fuel trim or pressure codes
Fix: In-tank fuel filter often neglected. Requires tank drop and complete fuel system service. If contamination reached injectors, those need cleaning or replacement. 4-7 hours labor for filter; add 8-12 hours if injectors involved.
Estimated cost: $600-3,500
Buy only with complete service records and a pre-purchase inspection by an AMG specialist; budget $3,000-5,000 annually for maintenance and prepare for the possibility of a five-figure engine rebuild.
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.