Miles or Maintenance: How Many Miles is Too Many for a Used Car?


Miles or maintenance? It’s a common question sent my way by viewers and readers alike: how many miles is too many for a given second-hand ride? Most recently, a family member was in touch to ask about buying a used, high-mileage Audi A5 Coupe. Just a few years old, this sporty two-door has an appealing asking price, though the mileage on the odometer did drum up some concern.

“Is that too many miles for this car?” he asked, after sending me the link to the used car ad.

Before continuing, I’m going to tell you something important: even the most reliable cars on the road can become a nightmare if they’re improperly maintained and cared for.

And still, the odometer reading of a used car is commonly held as the strongest indicator of the remaining life of the vehicle in question. Some folks hold certain brands and models as ‘safer’ to buy at higher mileage, perhaps based on past experience or the plethora of online reliability ratings which claim to know which used cars are the best.

Forget What you Know About Reliability

My opinion, formed after a decade of studying model-specific used vehicle reliability on a weekly basis, is that both of those concepts are flawed.


First, reliability rankings often (and incorrectly) assign a one-size-fits-all rating to an entire make and model of vehicle. As if every single one of these units will be in the same condition after some given length of time, perhaps 3 or 5 years.

Second, and more importantly, is that mileage is just one of several predictors of a vehicle’s condition and remaining service life. And far from the best one.

For the best indication of the overall fitness of the second-hand car you’re considering, and you’re wondering about mileage or maintenance, forget the odometer and which automaker built it, and track down the servicing records instead.

In the long term, the badge on the vehicle’s hood has little to do with how reliable a vehicle is. In modern cars, I’d argue that the odometer reading is of similarly low importance.

The Key to Long Life?

Key in ensuring that 3 or 6 or 10 year old car you’re considering is going to treat you (and your wallet) well?

Making absolutely sure it was properly, consistently, and continually cared for by all past owners, through its entire life. Miles or maintenance? Maintenance is key.

Fluid changes, inspections, ongoing maintenance and care, tune-ups, and dealer servicing are the best way to give a vehicle a healthy start, and to keep it ticking reliably for the long term. Miles or maintenance? We say maintenance.

You might think, for instance, that a used Toyota or Honda is a safe bet. Largely because these automakers have a generally-strong reputation for building some of the most reliable cars.

Sure. But what if the previous owner never changed the oil on time, skipped regular inspections and tune-ups, and failed to properly care for the cooling system because they convinced themselves that a cooling system flush and inspection was just a dealership money-grab?

Put another way, would you expect two identical used cars with identical build dates and mileage to be equally reliable if one of them was maintained poorly, and the other was maintained flawlessly? Because you shouldn’t.

Deceiving Appearances?

Also, don’t underestimate how poorly the average seller may have cared for their ride before trying to sell it to you.

They’ll vacuum the interior and wax the paint before you arrive for your test drive, but on a weekly basis, I encounter online discussions where owners seek approval in owner forums to skip or stretch regularly scheduled maintenance. Having convinced themselves that regular maintenance is not, in fact, important.

In one example I encountered recently, the owner of a popular luxury SUV asked the online owner’s community whether he’d be ‘safe to skip the factory-prescribed brake system inspection and servicing, and a transmission fluid flush and fill.

Skipping maintenance like this can cause accelerated part wear, can cause small problems to become big and pricey ones, and can even void remaining warranty coverage on the components in question.

Remember: warranty coverage does not cover problems that result from a failure to properly maintain the vehicle. Also, it’s bad for the vehicle’s resale value.

But owners like this are more common than you think—and you’re best to take steps to ensure you aren’t buying a second-hand ride from one of them.

When it comes to buying a used car you might be wondering if miles or maintenance is the key to happiness. We guide you in the right direction

Check Out The Service History

Thankfully, confirming that all maintenance is up to date in your miles or maintenance hunt is a relatively painless task that’s well worth the extra time and effort required.

Here’s how you do it.

First, you’ll need a printed copy of the vehicle’s service schedule. In every car, this is located near the back of the owner’s manual. On your test drive of a given used car, consider photographing this service schedule with your smartphone, and then print the image off at home.

Conversely, you can typically find this list of servicing requirements online, often with a quick Google search, or by visiting the website of the vehicle’s manufacturer.

Next, ask the seller to hand over all printed receipts and service records for inspection. Hopefully, they (and all previous owners) have kept these. Perhaps in the glovebox. If not, a dealer or service centre may be able to print or email the service records relating to that vehicle, at the owner’s request. This assumes the vehicle was exclusively maintained at a single location.

When it comes to miles or maintenance, a car’s service records are like a person’s medical records. They begin at birth and should, ideally, follow you around for the rest of your life.

In any case, the goal is to have a list of all service requirements in one hand, and a stack of receipts and paperwork confirming that they’ve been adhered to, in their entirety, in the other. Now, take a pencil and put a tick-box beside each of the servicing requirements you have documentation for.

If there are any gaps or missing service records, proceed with caution.

Buying a used vehicle without full service records is not advised. It puts a great big cloud of uncertainty over that vehicle’s reliability. Note, further, that if you need to make a warranty claim (if applicable), you’ll need to prove that all of the servicing is up to date—oil changes included.


A vehicle’s warranty is a two-way street, after all. If full service records are unavailable, assume that any remaining warranty coverage is null and void. Remember: warranty coverage is typically compromised or voided the moment any regularly-scheduled maintenance is skipped.

A car’s service schedule is, after all, a list of instructions for owners to follow, continually, in order to ensure a long and healthy life from that machine. They’re a sort of cheat-sheet for maximum long-term reliability.

In summation: if you’re worried about miles or maintenance, think less about the mileage on the odometer and avoid any used vehicle without full service records for maximum long-term peace of mind.