Recalls: Mercedes W164 ML 63 AMG
Overview
Manufacturers, or importers, issue recalls for defects or faults which have the potential to cause injury. Generally, manufacturers will inform the original buyers if their vehicle is subject to a recall and of the steps required to remedy the defect or fault. Please note that the recalls below (if any) are for Australian-delivered vehicles only. Furthermore, the number of recalls should not be taken as an indication of a model’s reliability or its safety more generally.
Recalls: Mercedes W164 ML 63 AMG
Mercedes-Benz W164 ML 63 AMG: accelerator pedal nuts
In September 2007, a recall was issued for Mercedes W164 M-Class vehicles due to one of both of the nuts securing the accelerator pedal missing or not having been fitted correctly (PRA 2007/9495).
Mercedes-Benz W164 ML 63 AMG: tailgate malfunction
In April 2009, a recall was issued for Mercedes W164 M-Class vehicles manufactured from July 2008 to March 2009 and fitted with a power-operated tailgate. During heavy rain or when using a high-pressure cleaning device, water could enter the trunk area via the tail light seals – this could cause moisture to enter the electronic control unit for the tailgate and cause it to malfunction; the tailgate control unit could also experience localised overheating (PRA 2009/10710).
Mercedes-Benz W164 ML 63 AMG: Takata airbag recall
In May 2018, a recall was issued for Mercedes-Benz W164 ML 63 AMG vehicles that were available for sale from 1 August 2006 to 30 September 2012. In these vehicles, the airbag inflator contained propellant wafers that could degrade over time due to high temperatures and humidity. In the event of a collision, the airbag could deploy too aggressively such that the metal inflator housing could explode/rupture and cause metal fragments to be propelled through the airbag cushion and towards vehicle occupants. These metal fragments could cause serious injury or fatality. For the VINs of the recalled vehicles, please see PRA 2018/16775.
2005-11 Mercedes-Benz W164 ML63 AMG: reduced braking performance
In May 2022, recall campaign RC3020/3020A was issued for 2005-11 Mercedes-Benz W164 ML63 AMG vehicles. In these vehicles, corrosion may affect the sealing of the brake booster, causing the brake booster to leak and a reduction in braking performance. In cases of very severe corrosion, hard braking may damage the brake booster and this could reduce braking performance. Both of these conditions increased the risk of a collision and injury to vehicle occupants and other road users. As part of the recall, Mercedes-Benz advised that owners should stop driving their vehicle immediately and contact an authorised Mercedes-Benz service centre to arrange an inspection as soon as possible. If signs of advanced corrosion were present, a diagnostic test would be performed and, if failed, the brake booster would be replaced. For the VINs of the recalled vehicles, please see REC-005438.
Problems and faults: Mercedes W164 ML 63 AMG
Overview
This section identifies potential problems, causes and fixes based on the experiences of owners and repairers, online sources and technical service bulletins. This information is provided solely for reference purposes and AustralianCar.Reviews recommends that only properly qualified persons carry out repairs or modifications. Furthermore, the number of items below should not be taken as an indicator of a model’s reliability or the frequency with which they may occur.
To report a problem or fault to the AustralianCar.Reviews team, please use the Contact Us form. Note that AustralianCar.Reviews does not offer advice on automotive problems or disputes; such enquiries will not receive a reply. For vehicles purchased from dealers after 1 January 2011, please see our Australian Consumer Law fact sheet.
M156 engine (ML 63 AMG): cylinder head bolt failure
For 6.2-litre M156 engines with engines numbers up to 1569xx 60 060658 (corresponding to engines produced from 2006 to the first half of 2010), the cylinder head bolts can stretch and snap.
The M156 engine has ‘torque to yield’ bolts which are designed to achieve a specific clamping pressure by being tightened to a specific torque and then turned a specific number of degrees. To achieve the intended clamping pressure, the upper section of the bolts is designed to stretch slightly. While the exact cause is unclear, it has been suggested that the design of the bolts, their metallurgy or corrosion causes them to stretch and snap.
The failure of one head bolt puts additional stress on the other bolts, causing further failures. The loss of clamping pressure allows coolant and oil to enter the combustion chamber; coolant can also be forced up through the failed head bolt locations into the top of the heads, causing white smoke and a rough idle. In severe cases, the cylinders can experience hydro lock, causing the piston to seize and destroying the entire engine.
Symptoms of head bolt failure are:
- Repeated low coolant levels;
- High oil level (from coolant getting into the oil);
- Illumination of the check engine light (CEL); and,
- White exhaust smoke (burning oil).
To test for head bolt failure, the coolant system could be pressurised and allowed to sit over night to see if the coolant level had dropped and if coolant was present in the oil.
In April 2011, Mercedes-Benz issued service bulletin LI01.30-P-051567 regarding broken cylinder head bolts for the M156 engine which caused coolant to enter the engine oil and/or the combustion chamber. The service bulletin identified the following symptoms:
- CEL (Check Engine Light) illumination;
- Misfire;
- Rough running; and,
- Low coolant indicator illumination.
To fix, the cylinder heads had to be removed so that the piston deck height could be measured. If the measurement from the top surface of the crankcase to the top surface of the piston was outside of specification (the maximum deck height was 0.23 mm), then the affected connecting rod with piston and bearings had to be replaced. As part of the repair, all cylinder head bolts and hydraulic tappets were to be replaced.
M156 V8 engine (ML 63 AMG): camshaft lobe and valve lifter wear
In a US class action – CEDRIC CHAN v. DAIMLER AG, MERCEDES-BENZ, MERCEDES-BENZ USA, LLC and MERCEDES-AMG GMBH – it was alleged that the combination of nodular cast iron camshafts and valve lifters made of 9310-grade steel resulted in premature wear of the M156 engine as a result of:
- the soft camshaft metal, and/or
- improper heat treating, and/or
- improper camshaft offset.
Specifically, the camshafts were designed so that the lobes would contact the valve lifters. When the camshaft lobes experienced wear, the surface would become rough or scored and no longer make contact with the lifters with the same precision – this would cause the lifters to wear prematurely, demonstrated by a gouged ring in the top of the valve lifter. The gouged ring wear on the buckets also indicated that the buckets were not spinning as intended. The result of this premature wear would be serious engine failure.
Symptoms of camshaft lobe and valve lifter wear include rattling or clattering noises on start-up. In service bulletin S-B 05.20/20b (produced in 2009), Mercedes-Benz acknowledged the problem of camshaft and valve tappet wear. Ultimately, the class action did not proceed due to the plaintiffs’ lack of standing.
Problems and faults: Mercedes W164 ML 63 AMG
- Harsh downshifts from second to first gear when braking may require a software upgrade, a revised valve body or both.
- Snapping or groaning noises from the steering column when turning may be due to the upper steering shaft bearing failing.
- Dashboard warnings about the suspension and brakes may be due to abrasion of the front wheel speed sensor wires.
- The power-operated tailgate may reverse directions when closing due to a loose bolt for the gas strut.
- The steering wheel buttons may stop working due to an internal short-circuit. To fix, the steering wheel may need to be replaced.
- Where fitted, the air suspension may stop working and an ‘Airmatic – Visit Workshop’ message may appear due to the wiring harness insulation rubbing off and the wire short-circuiting.
- The door mirrors may not fully retract or open due to a loose electrical connection or a lack of lubrication on their pivots.
- The heated front seats may stop working due to the signal acquisition module failing.
- The temperature in the cabin may be warmer or cooler than the temperature set by the climate control system – this may require the sun sensor to be adjusted.
- It may not be possible to reprogram the integrated garage door opener unless the existing program is erased, though the instructions may not be in the owner’s manual.
- To erase the existing program, press and hold the two outer transmitter buttons until the signal light flashes rapidly.
