Mercedes C-Class Service Schedule: Every Service Item by Model, Year & Engine

C-Class generations and their service needs

The C-Class spans three generations of modern models: the W204 (2007–2014), the W205 (2014–2021), and the W206 (2021–present). Each generation uses different engines with different service requirements. The W204 diesel uses the OM651, which needs careful oil specification and has a known timing chain weak point. The W205 diesel uses the OM654, which requires the later MB 229.71 oil spec and has AdBlue system vulnerabilities. The W206 introduces mild-hybrid petrol engines with 48V electrical systems and different service requirements. This guide covers all three generations. For specific oil specifications, see our oil guide. For gearbox details, see our 7G and 9G service guides.

Service A: what you get and when

Service A is due at 12 months or 15,500 miles (whichever comes first) and includes: engine oil and filter with the correct MB-spec oil, cabin/pollen filter replacement, full fluid level check (coolant, brake fluid, power steering, screen wash, AdBlue where fitted), visual brake inspection, tyre condition and pressure check, and Active Service System reset via Xentry. W204 diesel (OM651): requires MB 229.51 or 229.52 oil. W205 diesel (OM654): requires MB 229.71 0W-20 oil. W204/W205 petrol (M271/M274): requires MB 229.5 or 229.6 depending on year. Cost at an independent specialist: £249–£299 for W204, £269–£329 for W205/W206.

Service B: the comprehensive service

Service B is due at 24 months or 31,000 miles and includes everything in Service A plus: brake fluid replacement (mandatory every 2 years), engine air filter replacement, spark plugs on petrol engines (every 4 years/46,500 miles for most, or every 2nd Service B), and a more detailed inspection covering exhaust system, suspension components, steering joints, driveshaft gaiters, and seat belts. W204 C220 CDI Service B at an independent specialist: £379–£479. W205 C220d: £399–£499. Additional operations flagged by the Active Service System (e.g. "Service B4") add to the cost: diesel fuel filter £60–£100, panoramic roof lubrication £60–£100, charcoal filter £50–£80.

Major milestones: 40k, 60k, 80k, 100k miles

40,000 miles: automatic gearbox fluid and filter must be changed regardless of what the official schedule says. 7G-Tronic (W204): £250–£350. 9G-Tronic (W205/W206): £300–£450. 4MATIC models: transfer case fluid £80–£120. 60,000 miles: the timing chain should be inspected on M271 (W204 petrol) and OM651 (W204 diesel) engines. Camshaft adaptation values on Xentry should not exceed 5 degrees. Spark plugs on petrol engines are typically due at this mileage. 80,000 miles: the DPF should be checked for soot and ash loading. Injectors on OM651 engines should be balance-tested. Airmatic components on W205 models with air suspension should be inspected for leaks. 100,000 miles: coolant replacement (10 years/100,000 miles). The timing chain should be inspected again. The gearbox should have had at least two fluid changes by this mileage. The rear subframe on W204 models should be inspected for corrosion (a known issue covered by Mercedes extended warranty in some cases).

Cost comparison: independent vs main dealer

Over 4 years/60,000 miles, a C-Class needs approximately: two Service A, two Service B, one gearbox service, two brake fluid changes (included in Service B), one set of spark plugs (petrol), one diesel fuel filter (diesel), and one set of brake pads (front). Independent specialist total: approximately £2,200–£2,800 including all parts and labour. Main dealer total for the same work: approximately £3,800–£5,000. The saving at an independent specialist over 4 years is £1,600–£2,200 — enough to cover a set of tyres (£600–£900) and a major unexpected repair. The work is the same, the parts are the same, the digital service history is the same. The only difference is the invoice total.