Can a used car have too many kilometres on it?

If you’ve ever bought a second-hand car you’ll know the feeling. You’re searching the for-sale ads, you find the model you’re after in the colour you want, and it’s at the low end of your budget. Then you look at the odometer reading and your heart sinks.

Not so many years ago, this was a sensible response. Engines had a limited shelf-life and even buying a used car that had been pampered and well-maintained with 200,000km on the clock was likely buying into a host of reliability issues.

But technological improvements such as more precise manufacturing tolerances and synthetic oils have minimised wear and tear, which means a modern engine that is properly maintained will last much longer than its 20th century forebears.

The uptake of electric vehicles has further altered the used-car equation. With few moving parts, an electric motor requires minimal maintenance, but EVs bring other age-related concerns, such as diminished battery capacity and tyre wear.

We asked Peter Willis, director of buying at Carma, to provide some insights on the importance of mileage when buying a used vehicle.

Should a six-digit odometer reading still be a concern for the modern used car buyer?

Kilometres are an important indicator, but they shouldn't be the deciding factor when buying a used car. Condition, maintenance history, age and how the car has been driven are just as important. 

Is it fair to say high mileage isn't as much of a concern today as it was 20 or 30 years ago?

I think the gap between brands buyers know and trust and those they’re less familiar with is widening. There are more unfamiliar brands in the market today than ever before, which can make buyers more cautious. I’d say there is still just as much concern around high kilometres as there ever has been, but certain makes and models naturally carry more buyer confidence than others. 

Is a low-mileage vehicle generally preferable to one with higher kilometres?

It really depends on the vehicle’s age and kilometres travelled. For example, there’s a big difference between a one-year-old car with 5000km and one with 40,000km. Ultimately, age, kilometres and service history all need to be considered together. A car with higher kilometres that has been consistently well maintained can still be a good option and provide confidence to buyers. 

Is high mileage more of a concern in a petrol or diesel vehicle?

Diesel vehicles are often considered better suited to high kilometres, but petrol engines can be just as capable. For example, LandCruisers are well known for reaching 500,000km to 1,000,000km, and while many of these are diesel models, their petrol counterparts can also achieve similar distances with consistent servicing and proper maintenance. Ultimately, it comes down to the quality of the vehicle and how well it has been cared for throughout its life, rather than simply whether it runs on diesel or petrol. 

How do high-mileage electric vehicles compare to traditional combustion-engine vehicles? Do they have less wear and tear in the powertrain but more elsewhere? Are the battery and tyres the main concerns for EVs?

There are some early signs that EVs could be a better long-term option for people who regularly cover large distances, given they have fewer serviceable items and generally require less maintenance. With brakes, suspension and tyres for EVs being the main wear areas, there is potential for lower ongoing maintenance costs. As battery health becomes better understood and batteries become easier and cheaper to replace or refurbish, EVs could become an increasingly attractive option for high-kilometre drivers. 

Is there a cut-off point where a buyer should probably avoid a used vehicle no matter the price (e.g. 300,000km), or is it all about maintenance? What should buyers look for in that regard?

It really comes down to the vehicle’s maintenance history, condition and overall quality rather than a specific kilometre cut-off. That said, every car reaches a point where age and accumulated wear and tear can make ongoing maintenance and repairs increasingly expensive. This varies depending on the make and model, whether it has any known reliability issues and, most importantly, how well the car has been maintained throughout its life. Buyers should look for a consistent service history and evidence.