Mercedes-Benz E 63 AMG
5.5-litre V8 BiTurbo β AMG's first forced-induction V8 and the successor to the naturally aspirated M156. 525β585 hp depending on model, up to 900 Nm in the S version. The character is fundamentally different from the M156: instead of a high-revving scream, a brutal torque wave from 1,750 rpm. The sound is deeper, more bass-heavy, with a characteristic turbo hiss on lift-off. Less emotional than the naturally aspirated engine, but in a different league on the motorway β above 200 km/h the M157 still accelerates like others do at 100. Timing chain is the known Achilles heel: chain tensioner failure at 80,000β120,000 km, Mercedes has improved the design (non-return valve in cylinder head oil gallery). Piezo injectors are sensitive to fuel quality, service life 100,000β150,000 km. Turbos last 200,000+ km with proper warm-up and cool-down β shut off immediately after a motorway run and they'll fail significantly earlier. Warm up the engine, allow cool-down after hard use, oil changes every 10,000 km with 0W-40 β then 300,000 km is realistic.
525 hp BiTurbo sleeper β rear-wheel drive, perfect chassis
E 63 AMG W212 with rear-wheel drive: 525 hp, the chassis a benchmark. Phenomenal how it turns in, how long it stays neutral, how delicately it's tuned. ESP off is no problem, beautifully controllable. The M157 responds unbelievably cleanly and directly β not something you normally expect from Mercedes. Rear tyres gone every 5,000β10,000 km with spirited driving.
Engine Weaknesses 11
The timing chains on the M157 5.5L BiTurbo V8 stretch, especially on vehicles with frequent cold starts and short trips. Engine damage possible if chain jumps. Extensive repair on the V8.
Symptoms: Metallic rattling on cold start, camshaft position fault codes, rough running, in extreme cases engine damage
Under heavy use the piston rings on the M157 wear prematurely. Oil consumption above 1 L/1,000 km is possible. Engine overhaul required with advanced wear.
Symptoms: Rising oil consumption, blue smoke on acceleration, oil mist from exhaust, oil level warnings
The high-pressure fuel pump on the M157 can wear internally at high mileage. Pressure drop in the rail causes difficult starting and power loss.
Symptoms: Difficult starting, power loss under load, hesitation at high rpm, fuel pressure fault codes
The M157 is affected by known timing chain wear from 80,000β120,000 km. Mercedes retrofitted check valves in the oil supply passages (TSB LI05.20-P-057028).
Symptoms: Rattling on cold start, later also at idle, check engine light with camshaft fault codes, power loss
The oil pump gear on the M157 wears at high rpm and generates metal debris. Oil pressure drop leads to overheating and cylinder bore damage.
Symptoms: Oil pressure warning at high rpm, metallic knocking from lower engine, heavy oil consumption
Timing chain and tensioners wear prematurely, especially model years 2011β2013. Mercedes retrofitted a check valve in the oil passages of the cylinder head. Repair often in the four-figure range, worst case five figures.
Symptoms: Rattling on cold start, later also at idle, increased on acceleration; check engine light
The valve cover gaskets on the M157 V8 leak and allow oil to drip onto the hot turbochargers. Smoke and a burning smell are the result.
Symptoms: Oil smell and smoke from engine bay, oil drops visible on turbochargers, dropping oil level
The M157 uses Bosch piezo injectors that typically last 100,000β150,000 km. Aftermarket alternatives are not available.
Symptoms: Rough engine, uneven idle, elevated fuel consumption, individual cylinder fault codes
Electric auxiliary water pump for charge air cooling fails. Leads to reduced power in limp mode.
Symptoms: Power loss under high load, warning message on display, limp mode
Bosch piezo-ceramic injectors are sensitive to fuel quality and have a limited service life of approx. 100,000β150,000 km. Replacing all 8 injectors costs up to 3,000 EUR; repair is not possible.
Symptoms: Rough running, misfires, power loss, check engine light, poor cold-start behaviour
The wastegate flaps on both turbochargers rattle at cold start due to play in the linkages. Usually an acoustic issue only, rarely performance-related.
Symptoms: Metallic clattering on cold start for 1β2 minutes, disappears at operating temperature
Vehicle Weaknesses 13
Rear subframe rusts from the inside out. Faulty factory sealant allows water ingress. Flagged as safety-critical at MOT.
W212 steel rear subframe with powder coating cracks over time and allows moisture in. Rusts from the inside. Mercedes replaces as a goodwill gesture. Safety-critical.
Brake lines above the rear axle corrode through after 8β10 years. Brake fluid loss leads to brake failure. MOT refusal.
Rear axle corrodes through with age; suspension mounting points are flagged at MOT. Goodwill repairs possible but time-limited.
Brake lines corrode at two to twelve times the rate of comparable vehicles according to MOT data.
The rear axle is prone to severe rust-through from the inside at the weld seams of the subframe. The problem goes unnoticed for a long time. Mercedes granted goodwill replacements in some cases.
Worn joints and strut rod ends on the front axle are a recurring problem. Classic wear pattern at higher mileages.
Drain holes in the sills clog up; water collects and promotes rust from the inside.
Worn ball joints and strut top mounts on the front axle are a recurring problem. Individual owners reported multiple repairs.
The soft top tends to develop cracks in the fabric after about 10 years. Ignored cracks lead to water ingress, mould growth and control unit damage.
The drain channels in the sills clog regularly, causing water accumulation and corrosion in the sill area. Control units in the floor area can become damp.
Knocking and rattling from the front axle on uneven road surfaces. Causes: worn ball joints, anti-roll bar bushings.
The parking brake is regularly flagged at MOT. Corrosion from infrequent use causes it to seize or fail.