Oil change intervals: how many kilometres between services?

2026-09-20

Oil change intervals: how many kilometres between services?

Most modern petrol and diesel engines built after 2018 run on a manufacturer interval of 15,000 to 20,000 km or one year, whichever comes first. City driving, short trips and towing shorten that interval, often to 10,000 km. The figure that actually applies to your car is printed in its service book, not in a generic table — and an app like Autofy keeps that date where you can find it.

The honest answer: your car decides, not the internet

Every garage blog publishes a table. They disagree with each other, because the correct interval is not a general fact — it is a per-engine specification. A 1.2 petrol from 2015 and a 1.5 diesel from 2023 do not share a schedule.

What the ranges do tell you is the order of magnitude. According to AD, petrol engines are commonly serviced between 10,000 and 15,000 km, while modern diesels can run 20,000 to 30,000 km. Most post-2018 engines sit in a 15,000–20,000 km / 12 month window.

The rule that is always true: the first of the two limits wins. Whichever arrives first, distance or time, triggers the service.

Why time matters as much as distance

Engine oil does not only wear out from friction. It oxidises, absorbs combustion residue and loses additive performance while the car sits on the street. A car driven 4,000 km a year still needs its annual service — the oil in it is a year old.

This is the part drivers get wrong most often, and it is the reason the manufacturer prints "or 12 months" next to the kilometre figure.

What shortens the interval

Short urban trips. The engine never reaches full temperature, so fuel and water stay in the oil.
Towing or a loaded roof rack. Higher loads, higher temperatures.
Stop-start traffic. More running hours for fewer kilometres.
Very cold or very dusty climates.

If two or three of those describe your week, treat the lower end of your manufacturer's range as your real interval.

Finding your actual figure

Three places, in order of reliability:

The service book that came with the car, or the maintenance page in the owner's manual.
The manufacturer's service schedule, searchable by model and engine code on most brand websites.
The last invoice, which often prints the next due date and mileage.

Write it down once. That number does not change for the life of the engine.

The part that actually fails: remembering

Almost nobody forgets how to service a car. They forget when they last did. Six months later the honest answer to "when was your last oil change?" is a shrug, and the safe move — doing it again early — costs money for nothing.

That is the gap Autofy fills: you log the oil change once, and the app shows how many months have passed, flags the parts you have never recorded, and keeps the invoice with the car rather than in a drawer. See also our guide to the timing belt, the other interval that is expensive to get wrong.

Frequently asked questions

How many kilometres between oil changes? Between 10,000 and 20,000 km for most modern engines, depending on the manufacturer and how you drive. Short urban trips justify the lower end of that range.

Does an oil change expire if I barely drive? Yes. Oil ages by oxidation even in a parked car, which is why manufacturers add a time limit — usually one year — alongside the kilometre limit.

What happens if I skip one? Worn oil stops protecting the engine and clogs the filter. The damage is gradual and invisible until something expensive fails, which is why the date matters more than the symptom.