What to expect at a car service

Pull up at any decent garage for a service and the work usually follows a pattern. The technician drains the engine oil, fits a new oil filter and refills with the correct grade, replaces any other items that are due, and works through a checklist of safety and condition checks.

Exactly which items are due depends on your car's age, mileage and the manufacturer's schedule, so there is no single standard job. Here is what normally happens, what you can do beforehand and what to ask. We carry out servicing at Automaster, a garage at Longcombe Cross near Totnes, for petrol and diesel cars.

What is actually done during a car service?

The core of nearly every service is an oil and filter change. Old oil carries combustion by-products and loses its ability to protect the engine as it ages, so fresh oil is the most valuable single item. Depending on the schedule, other parts may be replaced too, such as the air filter, the pollen or cabin filter, spark plugs on a petrol engine and the fuel filter on a diesel.

Alongside the replacements, the garage inspects the car. That normally includes the brakes, tyres, lights, wipers, suspension, steering components, exhaust, battery and the levels of coolant, brake fluid and screen wash. The aim is to catch wear before it becomes a failure.

• Engine oil and oil filter replaced
• Air filter, cabin filter and spark plugs where due
• Brake pads, discs and fluid condition checked
• Tyres, lights and wipers inspected
• Fluid levels topped up and leaks looked for

What is the difference between an interim, full and manufacturer service?

Garages use different names, so always ask what a quote includes. An interim service is a lighter check, often an oil and filter change with a smaller inspection, and is aimed at higher-mileage drivers between larger services. A full service goes further, with more items replaced and a longer checklist.

A manufacturer-schedule service follows the specific list for your model. Your handbook or service book sets out what is due and when, and the intervals vary between makes. Some items, such as brake fluid or a cambelt, run on time or mileage intervals of their own, so they may not be part of every visit.

How should I prepare my car for a service?

Tell the garage about anything that concerns you. Noises, vibrations, a pull under braking, a warning light or a smell are all worth mentioning, because a service checklist will not necessarily cover a symptom you do not report. Bring the service book and any previous invoices so the technician can see what was last done.

Remove valuables and anything heavy from the boot, and make sure you have the locking wheel nut key if your car has one. If you have recently noticed a dashboard light, write down when it appears so the garage can connect it to the symptoms.

What happens if the garage finds extra work?

Inspections sometimes show something that needs attention, such as worn brake pads or a split rubber boot. A sensible garage tells you what it found, explains why it matters and asks before carrying out anything outside the agreed work. You should be able to ask what is urgent and what can wait.

Cost drivers for extra work include the parts, how long the job takes and how hard the part is to reach. If you are unsure, ask for a written quote, and ask to see the worn part if that helps you decide.

How often should my car be serviced?

Most manufacturers give a time and a mileage, and the sensible approach is to follow whichever comes first. Many cars use a yearly interval, but it depends on the vehicle, so check your handbook. If you cover few miles, the oil still ages, which is why time matters as well as distance.

Heavy use makes a difference. Lots of short trips, heavy loads, stop-start driving and dusty roads can justify servicing sooner than the book suggests. Ask your garage what suits the way you use the car.