Mazda 6 2.0 Skyactiv-G GJ

The Mazda 6 GJ shares engine mounts with the Mazda 3 BM platform, and these are known to fail from around 50,000-80,000 km. The mounts use a hydraulic fluid damper that can leak, losing its vibration-damping properties. The most commonly affected is the dogbone (torque) mount at the top of the engine. Symptoms include noticeable vibration at idle (especially with AC on), clunking when shifting from reverse to drive, and the engine visibly rocking when revved in gear with the brake held. All three mounts (left, right, and torque mount) often need replacement together. OEM mounts cost approximately €80-150 each, and an independent garage will charge around €200-400 for labour depending on how many are replaced. Dealer quotes can reach €500 or more. Using aftermarket performance mounts adds vibration.

Like all gasoline direct injection engines, the 2.0 Skyactiv-G sprays fuel directly into the combustion chamber rather than over the intake valves. Oil vapour from the PCV system coats the intake valve stems and hardens over time. Symptoms typically appear between 100,000-150,000 km: rough idle, slight misfires, hesitation on cold starts, and increased fuel consumption. Mazda's high 13:1 compression ratio helps keep valve temperatures high, which reduces carbon formation compared to some competitors. Walnut blasting costs approximately €300-500 at a specialist. Replacing or cleaning the PCV valve at around 80,000 km helps slow progression. Cars driven primarily on short urban trips accumulate carbon faster. Regular motorway driving at higher RPM helps delay the onset. Many owners reach 200,000 km without needing intervention.

Mazda issued TSB 01-019/19 acknowledging that the hydraulic drive belt auto tensioner can leak oil due to insufficient sealing at the damper under high ambient temperature and high load conditions. Symptoms include a rattling noise on acceleration and visible oil seepage around the tensioner. The modified replacement part (superseded to PE03-15-980C) has improved sealing. Replacement costs approximately €150-350 including the part and about one hour of labour. If the leak goes unaddressed, the serpentine belt can slip and accessories (alternator, power steering, AC compressor) lose function. The issue can appear from around 60,000 km onward. This affects all Skyactiv-G 2.0 applications including the Mazda 3 and CX-5.

This is the most commonly reported issue across all Mazda models using power folding mirrors, including the Mazda 6 GJ. The internal plastic gears degrade from repeated use and moisture ingress. One mirror typically fails first, with the other following within 6-12 months. Symptoms include grinding noises, stuttering, and incomplete folding. A full mirror assembly replacement at a Mazda dealer costs €350-500 per side. However, aftermarket repair kits with upgraded metal gears are available for €15-30 and can be fitted at a local garage for under €100 total. Disabling the auto-fold function via the mirror switch extends gear lifespan significantly.

Mazda issued TSBs for 2013-2016 Mazda 6 models identifying two causes of front suspension noise. First, the bump stopper contacts the strut bearing when the front shock absorber is compressed, causing a popping sound. Second, the front lower arm bushing makes a stick-slip noise in wet road conditions. Mazda revised the strut bearing material and added a dry coating to reduce bushing friction in later production. Replacement of strut top mounts costs €150-250 per side; lower arm bushing replacement runs €200-300 per side at an independent garage. The issue is annoying but does not affect safety or handling. Post-2016 facelift models are largely unaffected.

The oil control valves on the Skyactiv-G 2.0 use a rubber sleeve pressed into the valve cover. Over time, heat cycles cause the seal to harden and shrink, allowing oil to seep past. The leak is typically slow and visible when the engine cover is removed. For minor seepage, simply wiping it at each oil change is sufficient. If the leak worsens, replacement of the OCV and its seal costs approximately €100-200 for parts and €50-100 for labour. In some cases the valve cover gasket should be replaced at the same time. The issue can appear from around 80,000 km onward but is often cosmetic rather than serious.

Mazda issued a TSB for rear coil springs that can break at their lower side due to corrosion from dust and moisture trapped between the spring and the spring sheet. The right rear spring is most commonly affected. Symptoms include a knocking noise from the rear and the car sitting lower on one side. Mazda revised the spring shape in later production runs. Replacement costs approximately €200-400 for a pair of springs including labour. The issue primarily affects cars driven in regions with road salt and is most common on 2013-2015 production models.

Mazda issued TSB 01-009-14 for 2012-2014 Skyactiv-G 2.0 engines where foreign debris can become stuck on the oil pump pressure relief valve, causing a drop in oil pressure. If the oil pressure light illuminates, the engine must be stopped immediately to prevent bearing damage. The repair involves replacing the oil pump, oil strainer, and cleaning the oil pan. This costs approximately €400-800 at a specialist. The issue primarily affects early 2012-2014 engines and is relatively uncommon. Using the correct Mazda-specified oil filter is critical, as some aftermarket filters do not provide adequate filtration for this engine. Regular oil changes with quality 0W-20 oil reduce the risk.