Many drivers know their car needs servicing but aren't sure what exactly goes into a major service and how it differs from a minor one. The difference isn't just the price. A major service covers work that's done once every few years, and it directly determines how long your engine will last.
What is a major service and why it differs from a minor one
A minor service is an oil change, oil filter, air filter, and sometimes a cabin filter. It's done once a year or every 10,000 to 15,000 km and covers everyday wear. It's a routine that keeps the engine lubricated and clean.
A major service is a completely different level. It includes replacing the timing belt or inspecting the timing chain, replacing the water pump, flushing and refilling coolant, replacing brake fluid, replacing the auxiliary belt with its tensioner, and on petrol engines replacing the spark plugs. On top of that, there's a thorough inspection of the entire suspension, CV joints, brake discs and pads, and all rubber components on the engine.
In short, a minor service is routine maintenance. A major service is a comprehensive overhaul that prevents serious failures.
What exactly gets replaced and checked during a major service
The specific items depend on the engine type and manufacturer's recommendations, but a typical major service includes:
- Timing belt with the full kit (tensioner, guide pulleys) or timing chain inspection. This is the most critical item because on most modern engines, a snapped belt means destroyed valves and pistons.
- Water pump. Replaced together with the belt since the access is the same and the pump's lifespan is similar. There's no point paying for the same labour twice.
- Auxiliary (serpentine) belt and tensioner. Drives the alternator, AC compressor, and power steering pump.
- Coolant. A complete drain and refill. Over the years coolant loses its protective properties and starts causing corrosion in the cooling system.
- Brake fluid. It's hygroscopic, meaning it absorbs moisture from the air. Contaminated brake fluid has a lower boiling point and reduces braking effectiveness.
- Spark plugs (on petrol engines). Worn plugs cause hard starting, higher fuel consumption, and rough engine performance.
- Detailed inspection of brakes, CV joints, wheel bearings, hoses, and all rubber components. A major service is the opportunity to assess the condition of everything that isn't visible on the surface.
Of course, every car has its specifics. Cars with a timing chain instead of a belt don't have that same item, but chains have their own symptoms and inspection intervals. There's a separate guide on that topic on our site.
At how many kilometres is a major service due
The most common interval is between 60,000 and 120,000 km, or 4 to 6 years, whichever comes first. The exact interval depends on the manufacturer and engine type. Some examples:
- VW/Audi/Skoda 1.9 TDI: timing belt at 120,000 km or 5 years.
- Fiat 1.3 MultiJet: belt at 60,000 km or 4 years.
- Renault 1.5 dCi: belt at 90,000 to 120,000 km, depending on the engine version.
- Ford 1.6 TDCi: belt at 160,000 km, but earlier inspection is recommended.
It's important to understand that the time limit applies even if you haven't reached the mileage. A rubber belt ages and becomes brittle after 5 to 6 years regardless of how much you've driven. The same goes for coolant and brake fluid, which degrade over time, not just with mileage.
We covered timing belt and chain details, including symptoms of a stretched chain and intervals by manufacturer, in our guide on timing chain and belt replacement.
What happens when you skip a major service
The consequences are serious and almost always more expensive than the service itself.
A snapped timing belt is the worst-case scenario. On interference engines (and that's the vast majority today) the pistons hit the valves and the engine suffers severe damage. The repair costs many times more than a preventive belt replacement.
Engine overheating occurs when the water pump starts leaking or the coolant loses its properties. An engine that overheats even once can end up with a blown head gasket, a warped head, or permanently damaged cylinders.
Reduced braking is a silent problem. Brake fluid with too much moisture doesn't respond the same under pressure. You won't notice it during normal driving, but during hard braking at higher speeds the difference can be critical.
A chain of expensive repairs. A neglected auxiliary belt can damage the alternator. Worn spark plugs can overload the ignition coils. One skipped job pulls a whole series of other failures behind it.
How to know it's time for a major service
The most reliable approach is to follow the service booklet or records of previous services. If you know when the belt was last replaced and how far you've driven since, it's easy to estimate.
The problem arises with used cars, especially imports. Service history is often lost during ownership transfers, and the previous owner leaves no documentation. If you've bought a used car and have no record of a major service, the safest approach is to assume it was never done and do it right away. It's better to replace a belt that might still be fine than to risk it snapping while driving.
Some signs that a major service is overdue:
- The engine is hard to start or runs rough on cold starts.
- You hear squealing or hissing from the front of the engine (auxiliary belt).
- The coolant has changed colour or contains sediment.
- The brake fluid is dark or its level has dropped below the minimum.
- The service sticker shows a mileage figure that's long been passed.
When a car comes in for a major service, we always replace the full kit. Belt, tensioner, guide pulleys, and water pump together, because the access is the same and labour is the most expensive part. Splitting those jobs across two visits makes no sense. Part quality has to be up to standard too, because a cheap belt of unknown origin defeats the entire purpose of the service.
If you're not sure whether your car is due for a major service, stop by the workshop. We'll check the condition and tell you exactly what's needed.