The underrated Japanese executive that outlasts German rivals
Mazda's D-segment saloon and estate has been a compelling alternative to the Mondeo and Passat since 2002, now in its third generation. Depreciation of around 48% after five years makes it excellent used value — 2018 models from £12,000, older Mk3 cars from £6,000. The SKYACTIV 2.2 diesel delivers up to 62 mpg with strong performance. Consistently praised for driving dynamics that rival BMW 3 Series.
We track 6 known issues across the Mazda 6 range, including 1 rated as safety-critical. Knowing which variants and configurations to approach with caution can save you from expensive surprises after purchase.
Found a Mazda 6? Enter the reg to see which of our 6 known issues apply to that exact car, plus full MOT history and mileage checks.
GG (2002–2008) — Petrol options included the 1.8 MZR, 2.0 MZR, 2.3 MZR, with 2.0 MZR-CD on the diesel side.
GH (2008–2013) — Petrol options included the 1.8 MZR, 2.0 MZR, 2.3 MZR, with 2.0 MZR-CD on the diesel side.
GJ (2008–2018) — Petrol options included the 2.0 Skyactiv-G, 2.5 MZR, with 2.2 MZR-CD, 2.2 Skyactiv-D on the diesel side. Our database flags 5 known issues on this generation, 1 of which are rated as safety-critical. The most significant concern is Subframe and suspension mounting point corrosion (£800–£2,500 to address).
The Mazda 6 suffers from severe corrosion around subframe mounting points and suspension component attachment areas. The steel subframe and surrounding chassis areas are inadequately protected from salt water ingress, leading to structural corrosion that compromises vehicle rigidity and suspension mounting integrity. This affects both generations but is particularly severe on 2002-2008 models. MOT data shows this model failing at up to 94.7 times the national average for suspension component corrosion and 58.4 times the average for mounting point corrosion. The issue worsens progressively and represents a genuine safety risk.
Severe corrosion can lead to suspension components detaching from the body shell, causing immediate loss of vehicle control and potentially fatal accidents. Even moderate corrosion represents an MOT failure and requires immediate welding repair. Repair costs typically range from £800-£2,500 depending on the extent of corrosion, but many cars become uneconomical to repair.
Inspect the wheel arches, sills, jacking points and door bottoms carefully. Press gently on sills to check for soft spots. Look underneath for corrosion on structural components. Check the MOT history for corrosion-related advisories or failures.
The diesel particulate filter (DPF) on 2.2-litre diesel Mazda 6 models suffers from frequent blockage issues, particularly when used for predominantly short urban journeys. The DPF requires regular high-temperature regeneration cycles to burn off accumulated soot particles, but insufficient motorway driving prevents this process. The SH-VPTS Skyactiv-D engine is particularly affected due to its advanced combustion system producing fine soot particles. Blocked DPF causes excessive smoke emission, reduced power, and eventual engine protection mode activation.
A completely blocked DPF will put the engine into limp mode, limiting power and speed. Professional DPF cleaning costs £300-£500, while DPF replacement costs £1,200-£2,000. Continued driving with a blocked DPF can damage the turbocharger and require engine internal cleaning.
Ask about the car's typical usage — short urban journeys prevent DPF regeneration. Check for DPF warning lights and ask about any previous regeneration issues. A forced regeneration at a garage costs far less than a DPF replacement.
The rear suspension trailing arm bushes and lateral link bushes on the Mazda 6 deteriorate prematurely due to their rubber composition and exposure to road contaminants. This is separate from the structural corrosion issue but contributes to the high MOT failure rates for suspension components. Worn bushes cause imprecise rear axle location, leading to poor handling, tyre wear, and eventual MOT failure for excessive movement in suspension components.
Worn bushes cause progressive handling deterioration and uneven tyre wear. The car remains safe to drive but will eventually fail an MOT test. Full rear bush replacement typically costs £400-£800 depending on which bushes require replacement.
Listen for knocking, clunking or rattling over bumps during the test drive. Inspect the underside for corroded or cracked suspension components. Check the MOT history for suspension-related advisories, which often predict future failures.
The rear parking brake cables on the Mazda 6 are prone to corrosion and stretching, leading to poor handbrake efficiency that fails MOT requirements. The cables run under the car and are exposed to road salt and water, causing the inner cable to seize within the outer sheath. This affects all variants but is particularly common on cars used in areas with heavy winter salt use. MOT data shows this model failing at 27.3 times the national average for parking brake efficiency.
Poor handbrake efficiency causes an MOT failure and represents a safety risk when parking on slopes. Cable replacement typically costs £200-£400 for both sides. If left unaddressed, the cables can seize completely, requiring rear brake disc removal for replacement.
Check brake disc condition for lipping or scoring. Test braking at moderate speed for pulling to one side or vibration through the steering wheel. Review MOT advisories for brake-related items.
The first-generation Mazda 6 petrol engines (1.8, 2.0, and 2.3 MZR units) develop excessive oil consumption as they age, typically above 80,000 miles. This is caused by worn piston rings and valve stem seals allowing oil to enter the combustion chambers. The 2.3-litre L3-VE engine is particularly affected. MOT data shows these engines failing emissions tests at significantly higher rates due to oil burning producing blue smoke during acceleration.
Excessive oil consumption requires regular oil top-ups and eventual engine rebuild or replacement. Cars with severe oil burning will fail MOT emissions tests. A complete engine rebuild costs £2,000-£4,000, while a replacement used engine costs £1,000-£2,000 plus fitting.
Check the oil level before the engine is started. Ask the seller how often they top up the oil between services. After a test drive, check the level again and look behind the car for blue or grey exhaust smoke under acceleration.
For the full breakdown of all 6 tracked issues with repair costs, see the Mazda 6 common problems page.
Based on 381k real DVSA MOT tests, the Mazda 6 fails more often than average on several items. The biggest outlier is anti-roll bar links worn at 95x the fleet average, followed by headlight fault (76x).
When viewing a specific car, check its MOT history for recurring advisories in these categories. See the full Mazda 6 MOT failure breakdown for data at every mileage point.
Routine servicing (oil and filter change every 13k miles) typically costs £80–£120 at an independent garage.
The bigger-ticket items to budget for include timing belt (£400–£600).
See the full Mazda 6 service schedule for every interval and cost breakdown.
The Mazda 6 has some well-documented weak points, including 1 safety-critical issue that demand careful checking. The right example, properly maintained, can still be a sound purchase — but cutting corners on the pre-purchase inspection is not advisable. 2018-2021 Mk3 facelift models are the safest choice — Mazda upgraded the interior to near-premium quality and refined the SKYACTIV 2.2 diesel further. The 2.0 SKYACTIV-G petrol with manual gearbox is the most reliable powertrain. Avoid 2003-2004 Mk1 models (severe engine problems reported around 98,000 miles) and 2006-2010 Mk2 cars with automatic gearboxes. A clean 2017 Mk3 with full service history is the budget sweet spot.
Before committing, check the car's full MOT history, verify the service record is complete, and if possible arrange a specialist inspection. Enter any registration into our free report to see the complete picture.
Get Car Wise maintains a database of known mechanical issues for every popular car on UK roads, tracking the faults that owners, specialists and DVSA data reveal.
When you run a report on a specific Mazda 6, we cross-reference the exact variant, engine and age against our database of 6 known issues. Combined with full MOT history analysis, mileage verification and DVLA data, you get a complete picture before viewing.
Enter the registration for MOT history, mileage verification, known faults for that exact variant, and a Get Car Wise Score.
This guide was compiled from independent expert reviews, DVSA MOT data, specialist workshops and our own database of 6 known Mazda 6 issues. We are not affiliated with any source listed.