Mercedes-Benz AMG G 63
The M177 is AMG's most widely used V8 biturbo today and is considered technically mature and long-lived. The hot-V turbocharger arrangement delivers spontaneous response with barely perceptible lag. Weaknesses are manageable: wastegate rattle in cold weather, ignition coil recall for early 2015 model years, valve cover gaskets with age. Regular oil changes with attention to oil quality deliver a very robust engine. In direct comparison with the M156 less emotional, but significantly more reliable and efficient.
585 hp fortress — the V8 as an acoustic earthquake on wheels
23 months wait on order — because everyone wants one. In Dynamic mode deep, rich V8 sound through 2,560 kg of off-roader. The M177 feels here not like a sporting engine but like a power station in a fortress. 16 L/100 km at gentle country road pace, 1 litre of oil per 2,000 km during the run-in phase is normal. A-pillar rust from the factory documented, headlining detaches. Universally well received — unrivalled exterior presence.
Engine Weaknesses 8
The MCT Speedshift gearbox (wet launch clutch instead of torque converter) wears the clutch significantly faster in frequent stop-and-go. Clutch replacement requires gearbox removal.
Symptoms: Judder on pull-away, clutch slip at full load, gearbox warning message, delayed engagement from standstill
Identical issue to the M176/M278: the solenoid leaks, oil migrates by capillary action through the wiring harness. On AMG vehicles this is even more frequent due to higher oil temperatures.
Symptoms: Cold-start rattle, camshaft adjuster fault code, oil traces on connector, potential ECU consequential damage
The camshaft cover gaskets on the M177 AMG V8 become brittle from the high heat exposure in the hot-V. Oil escapes onto turbochargers and exhaust system.
Symptoms: Oil smell on hot engine, oil film on turbochargers, smoke from engine bay
The M177 has several electric auxiliary coolant pumps for charge air cooling. These fail and lead to elevated charge air temperatures with power reduction.
Symptoms: Power reduction during spirited driving, cooling system fault codes, elevated charge air temperature
The camshaft adjuster solenoids on the M177 can leak internally or stick. Fault codes for camshaft position and rough running are the result.
Symptoms: Check engine light, rough idle, camshaft position fault codes, power loss in the lower rev range
Vehicles with M177/M178 engines built between Jan. and Nov. 2015 had faulty ignition coils that caused misfires. Mercedes replaced affected parts under a recall.
Symptoms: Rough idle, misfires, check engine light, occasional limp mode
The wastegate flaps of the BiTurbo system clatter briefly after cold start. Normally disappears after a few seconds. With prolonged operation replace the wastegate actuator.
Symptoms: Metallic clattering directly after cold start, disappears after warm-up, permanent with wear
As a direct-injection engine without port injection, carbon residues build up on the intake valves. Walnut blasting every 50,000–80,000 km recommended. Performance loss is gradual.
Symptoms: Gradually roughening idle, slight power loss, elevated fuel consumption
Vehicle Weaknesses 7
On vehicles with DISTRONIC PLUS, a CAN bus fault can interrupt coordination between DISTRONIC and ESP. The vehicle then maintains its current speed regardless of the situation.
At warm ambient temperatures a faulty brake control unit can trigger limp mode with a brake fault warning. Affects W463a from 2019. Replacement of the control unit required.
The window channel rubbers are not painted inside from the factory and often begin to rust within a few years. Window frames, roof rails and tailgate hinges are all at risk.
On the W463a, moisture can penetrate headlights and other lamp units. Without immediate resealing, secondary electrical damage follows.
MBUX system shows sporadic software and connectivity issues. Diagnosis complicated by Xentry system as proprietary protocols restrict external diagnostic tools.
The MBUX system occasionally freezes or becomes unresponsive. Climate control and seat adjustments can be partially affected. Software updates resolve some issues.
Thin paint layer and poor door panel finish reported. Warranty claims are occasionally rejected.