.png){kind=small}
The Mercedes G-Class W463 G 55 AMG Kompressor is one of the most iconic SUVs ever produced. It combines rugged off-road capability with the high-performance engineering expected from AMG.
However, despite its reputation for durability and power, this model is not without its problems. Owners of the G 55 AMG Kompressor often encounter a range of mechanical, electrical, and structural issues that can lead to costly repairs.
In this article, we will explore the most common problems of the Mercedes G-Class W463 G 55 AMG Kompressor, helping owners and potential buyers understand the challenges that come with owning this powerful SUV.
Mercedes G-Class W463 G 55 AMG Kompressor Supercharger and Engine Issues
Supercharger Failure
One of the defining features of the G 55 AMG Kompressor is its supercharged 5.4L V8 engine (M113K). While this engine delivers impressive power, the supercharger system is known to develop problems over time.
Some of the most frequently reported issues include:
Supercharger clutch failure – The electromagnetic clutch that engages and disengages the supercharger can fail, leading to a loss of boost pressure and reduced engine performance.
Worn-out supercharger bearings – Over time, the bearings inside the supercharger wear out, causing a whining noise and eventual failure.
Belt slippage or tensioner failure – The supercharger belt is under significant stress, and if the belt tensioner fails, the belt can slip, reducing boost levels.
Routine maintenance and periodic supercharger inspections can help prevent catastrophic failure. Owners should listen for abnormal whining sounds or power loss, which may indicate an issue with the supercharger.
Coolant System Leaks
The cooling system in the G 55 AMG Kompressor is under intense stress due to the high-performance engine.
Common coolant-related issues include:
Leaking radiator – The plastic components of the radiator degrade over time, leading to coolant leaks and overheating.
Water pump failure – A failing water pump can cause the engine to overheat, leading to expensive repairs.
Cracked coolant hoses – The intense heat from the supercharged V8 can cause coolant hoses to crack, leading to leaks.
Frequent coolant level checks and replacing worn components before they fail can help maintain engine temperature and prevent damage.
Oil Leaks and Gasket Failures
The M113K engine is notorious for oil leaks, which are often caused by:
Valve cover gasket leaks – Over time, the valve cover gaskets harden and begin to leak oil.
Oil cooler seal failure – The oil cooler seals tend to degrade, leading to oil seepage around the engine bay.
Front crankshaft seal leaks – The front seal can wear out, allowing oil to leak onto the serpentine belt.
Regular inspections and prompt gasket replacement can prevent oil leaks from causing further issues.
Mercedes G-Class W463 G 55 AMG Kompressor Transmission and Drivetrain Problems
5G-Tronic Transmission Issues
The 5-speed automatic transmission (722.6) in the G 55 AMG Kompressor is generally reliable, but owners have reported several problems, including:
Delayed gear shifts – A sluggish response when shifting gears is a common complaint, often caused by low transmission fluid levels or a failing valve body.
Harsh shifting – Rough or jerky shifts can indicate worn-out transmission mounts or solenoid failure inside the valve body.
Torque converter issues – The torque converter can fail, leading to symptoms like shuddering, slipping, or loss of power.
Routine transmission fluid changes and proper servicing are essential to prevent premature wear.
Transfer Case and 4WD System Failures
Since the G 55 AMG Kompressor is a full-time 4WD SUV, its transfer case and differential system are crucial for its performance.
However, common issues include:
Transfer case leaks – The seals inside the transfer case wear out, leading to fluid leaks.
Differential noise – The front and rear differentials are prone to developing whining or grinding noises, indicating worn bearings or low fluid levels.
Electronic shift actuator failure – The actuator responsible for engaging low-range mode can fail, making it impossible to switch driving modes.
Routine differential fluid changes and transfer case inspections can prevent costly failures.
Mercedes G-Class W463 G 55 AMG Kompressor Suspension and Steering Issues
Air Suspension Failures
The G 55 AMG Kompressor uses an adaptive air suspension system, which provides an excellent ride but is known for frequent failures.
Common problems include:
Air strut leaks – The air struts tend to develop leaks, causing the SUV to sag or sit unevenly.
Compressor failure – The air suspension compressor may fail prematurely, leading to suspension collapse.
Valve block issues – The suspension’s valve blocks can malfunction, affecting ride height adjustments.
Replacing air suspension components can be expensive, leading some owners to convert to a coil spring setup for increased reliability.
Steering Rack and Tie Rod Wear
Owners have reported issues with the steering system, including:
Excessive play in the steering wheel – The steering rack can develop play over time, making the vehicle feel unstable at higher speeds.
Tie rod end wear – Worn tie rod ends cause alignment issues and uneven tire wear.
Power steering leaks – Leaks in the power steering system can result in a heavy or unresponsive steering feel.
Regular steering component inspections and fluid changes can prevent major repairs.
Mercedes G-Class W463 G 55 AMG Kompressor Electrical and Electronic Failures
Alternator and Battery Drain Issues
The G 55 AMG Kompressor has an extensive electrical system, and owners frequently experience battery drain issues due to:
Faulty alternator – The high-powered AMG engine requires a strong alternator, but failures are common, leading to charging system problems.
Parasitic battery drain – Many owners report excessive battery drain overnight, often caused by faulty control modules or malfunctioning relays.
Using a battery tender or upgrading to a high-performance AGM battery can help mitigate these issues.
Central Locking and Window Regulator Failures
Electrical components in the G 55 AMG Kompressor are known to fail, particularly:
Central locking system malfunctions – The actuators inside the doors can fail, preventing doors from locking or unlocking properly.
Window regulator failures – The power window regulators frequently break, leaving the windows stuck open or closed.
Replacing door lock actuators and window regulators with OEM or high-quality aftermarket parts is a common fix.
Mercedes G-Class W463 G 55 AMG Kompressor Brake System Problems
Premature Brake Wear
The Mercedes G 55 AMG Kompressor is a heavy and powerful SUV, which places significant stress on its braking system.
Many owners report premature brake wear, particularly with:
Front and rear brake pads – Due to the vehicle’s weight and aggressive driving styles, brake pads tend to wear out faster than expected.
Brake rotors warping – The high-performance braking system generates a lot of heat, which can cause the rotors to warp over time, leading to brake judder and vibrations.
Sticking brake calipers – The AMG-specific Brembo brake calipers sometimes develop sticking issues, resulting in uneven brake pad wear and reduced braking performance.
Routine brake inspections and high-quality brake components are necessary to maintain optimal stopping power.
ABS and Brake Sensor Failures
The Anti-lock Braking System (ABS) and brake sensors are essential for safety, but common issues include:
Faulty wheel speed sensors – The wheel speed sensors can fail, triggering ABS warning lights and affecting traction control.
Brake light switch failure – A failing brake light switch can lead to intermittent brake light operation and even prevent the car from shifting out of park.
Hydraulic brake booster leaks – Some models experience leaks in the brake booster, reducing braking efficiency.
Addressing sensor failures early can prevent larger brake system issues.
Mercedes G-Class W463 G 55 AMG Kompressor Body, Chassis, and Rust Problems
Rust on Frame and Body Panels
Despite its military-grade construction, the G 55 AMG Kompressor is prone to rust, especially in areas with harsh winters or high humidity.
Common rust-prone areas include:
Underbody and frame – The frame and undercarriage are susceptible to rust, especially near welds and suspension mounts.
Door hinges and wheel arches – The exposed metal around door hinges and wheel arches often shows early signs of corrosion.
Rear door and tailgate – Water accumulation in the rear spare tire mount area leads to paint bubbling and corrosion.
Applying rust protection treatments and regular undercarriage washing can help slow down rust progression.
Door and Window Seal Leaks
Many G 55 AMG Kompressor owners report water leaks due to deteriorating door and window seals. This leads to:
Water pooling in the footwells – A common issue after heavy rain, especially when drain channels get clogged.
Wind noise at high speeds – Aging rubber seals around the windows and sunroof often lead to excessive wind noise.
Mold and interior damage – Prolonged water exposure causes mold growth and damages the leather upholstery and carpets.
Replacing rubber seals and keeping drainage channels clean prevents major interior damage.
Mercedes G-Class W463 G 55 AMG Kompressor HVAC and Climate Control Failures
Air Conditioning and Heater Problems
The climate control system in the G 55 AMG Kompressor is powerful but often develops issues, including:
Weak air conditioning performance – A failing AC compressor or refrigerant leaks lead to reduced cooling.
Blend door actuator failures – The actuators controlling hot/cold airflow get stuck, causing inconsistent cabin temperatures.
Defective blower motor – Owners report that the blower motor sometimes fails completely or works intermittently.
Routine HVAC servicing and replacing worn actuators can restore proper climate control.
Heated Seat and Ventilation System Malfunctions
Luxury features such as heated and ventilated seats are prone to failure, including:
Heated seat elements burning out – The heating elements in the seats wear out over time, requiring full seat disassembly for repairs.
Ventilated seat fan failures – The seat ventilation system clogs with dust, reducing cooling performance.
While these features enhance comfort, repairs can be expensive due to the need for seat dismantling.
Mercedes G-Class W463 G 55 AMG Kompressor Fuel System and Exhaust Issues
Fuel Pump and Injector Failures
Given its high-performance supercharged engine, the G 55 AMG Kompressor requires precise fuel delivery, but common issues include:
Failing fuel pump – Leads to engine hesitation, hard starting, or power loss under acceleration.
Fuel injector clogs – Can cause misfires, rough idle, and poor fuel economy.
Regular fuel system cleaning and using high-quality gasoline can prolong the life of the fuel injectors and pumps.
Exhaust Manifold and Catalytic Converter Failures
The exhaust system is another area where G 55 AMG Kompressor owners report problems, such as:
Cracked exhaust manifolds – Heat cycling causes the exhaust manifolds to crack, leading to an annoying ticking noise and power loss.
Catalytic converter failure – Due to carbon buildup and overheating, the catalytic converter can clog and trigger a check engine light.
Replacing cracked manifolds and ensuring a clean-burning fuel mixture helps prevent major exhaust failures.
Mercedes G-Class W463 G 55 AMG Kompressor Final Thoughts
The Mercedes G-Class W463 G 55 AMG Kompressor is an iconic SUV that offers a mix of luxury, power, and off-road capability.
However, as we’ve explored, it has several common issues, including:
Supercharger and engine problems
Transmission and drivetrain failures
Suspension and steering issues
Electrical and electronic malfunctions
Brake system wear
Rust and body deterioration
HVAC and climate control failures
Fuel and exhaust system concerns
While many of these problems can be addressed with regular maintenance, G 55 AMG Kompressor owners should be prepared for higher repair costs due to the complex AMG components.
If you own a Mercedes G-Class W463 G 55 AMG Kompressor and need expert servicing, repairs, or diagnostics, visit us at:
European Auto Pro 253 Goodwood Road, Kings Park, 5034 South Australia
Our team of Mercedes-Benz specialists can help diagnose and fix any issues, ensuring your G 55 AMG Kompressor continues running smoothly for years to come.