What to Check Before Buying a High-Mileage Used Vehicle

By: Jason Brooks Last updated: 02/14/2025

(Image via Unsplash / JD Weiher)

Buying a used car, especially one with high mileage, can be a smart move when you’re on a budget or if you're buying a car for a first-time driver. High-mileage vehicles often come with a much lower price tag, making them an attractive option. However, a car that's traveled many miles requires extra scrutiny. High mileage shouldn't automatically mean a vehicle will give you problems, but it does increase the chances of wear and tear. That’s why it’s so important to do your homework and inspect every detail before making a purchase. To help you avoid costly surprises, we’ve put together a guide on what you should check before buying a high-mileage used vehicle. With these tips in mind, you’ll shop smarter and drive safer.

1. Check the Vehicle's Service History

A detailed service history is one of the most valuable pieces of information you can get when buying a used car. It tells you how the car has been maintained over the years and gives you a sense of its overall health. Look for regular maintenance records, such as routine oil changes, tire rotations, and recommended service checkups. A high-mileage car that’s been well-cared for is often a better purchase than a low-mileage car that's been neglected.

What to Look For:

Does the service history show consistent maintenance?
Has the car undergone major repairs, like engine work or transmission replacement?
Were any recalls addressed by the previous owner?

If the seller can’t provide the service records, that’s a red flag. Be cautious about purchasing cars without records.

2. Inspect the Engine

The engine is a vehicle's heart, and it’s especially crucial to ensure it’s in good condition for high-mileage cars. Higher mileage means the engine has worked hard, and neglect can lead to significant problems. When inspecting the engine, check for signs of leaks, unusual noises, or odd smells.

What to Check:

Open the hood and look for oil leaks or fluid stains.
Listen to the engine while it’s running. Does it sound smooth? Or are there knocking, pinging, or excessive revving noises?
Check the oil dipstick. Dirty or sludgy oil can signal poor maintenance.

Have a trusted mechanic inspect the engine for you. It’s always worth it to get professional advice.

3. Look at the Transmission

The transmission is another critical and costly part of a car. High mileage can mean wear and tear on both automatic and manual transmissions. A failing transmission often leads to expensive repairs, so take the time to evaluate its condition.

Signs of Problems:

For Automatics: Check for delayed shifting or jerking when the car changes gears.
For Manuals: Make sure the clutch engages smoothly and doesn’t slip.

It’s also a good idea to test-drive the car on different types of roads to see how the transmission performs in various conditions.

4. Inspect the Suspension System

A car’s suspension system affects its comfort and handling. Over time, components like shocks, struts, and springs can wear out, especially on a high-mileage vehicle.

What to Watch For:

Drive the car over speed bumps or uneven roads. Does it feel bouncy or uncomfortable?
Listen for clunking or squeaking noises as the car moves. These can signal worn-out suspension parts.

The suspension may need repairs if the ride feels rough or the car dips excessively when braking.

5. Assess the Tires

Tires can tell you a lot about a car’s condition. Uneven or excessive wear on the tires isn’t just a sign that new ones might be needed. It could also indicate alignment or suspension issues.

What to Do:

Check the tread depth using the penny test. Insert a penny into the grooves of the tire with Lincoln’s head facing upside down. Being able to see the top of his head means the tread is too worn.
Look for uneven wear patterns, such as more wear on one side of the tire.
Don’t forget to inspect the spare tire for damage or wear.

6. Evaluate the Brakes

Brakes are a non-negotiable aspect of car safety, and they tend to wear out faster in higher-mileage vehicles. Pay attention to how the brakes feel and listen for unusual noises.

What to Check:

Do the brakes respond quickly and smoothly?
Listen for grinding, squealing, or clicking sounds, which could mean the pads or rotors need replacing.
Check if the car pulls to one side when braking because that could signal an issue with the brake system.

Brake work can quickly become expensive if repairs are needed, so factor that into your decision.

7. Test the Electronics and Features

High mileage means the car has been used extensively, increasing wear on all components, including electronics and features.

Don’t Skip:

Check all the lights (headlights, taillights, turn signals, etc.).
Test the dashboard and infotainment systems. Any error messages or flickering screens?
Turn on the A/C and heat to make sure they work properly.

Small fixes can add up, so knowing what needs attention will help you better assess the car.

8. Examine for Rust and Corrosion

Rust isn’t just a cosmetic issue; if left unchecked, it can compromise the car’s structural integrity. Focus on key areas where rust is most likely to appear, especially in vehicles driven in snowy climates.

Key Inspection Points:

Check under the car, especially around the wheel wells and exhaust system.
Look at the door frames, trunk, and under the hood for signs of corrosion.

If you find rust in vital areas like the frame or undercarriage, it could mean the car has limited life left.

9. Dig into the Vehicle History Report

A vehicle history report is a must before buying any used car, but it’s especially crucial for high-mileage vehicles. This report can give you a clearer picture of the car’s past, including accidents, flood damage, and ownership history.

What to Look For:

Does the car have a clean title?
Has it been in any major accidents?
Are the odometer readings consistent with the mileage advertised?

Sites like Carfax and AutoCheck offer vehicle history reports for a fee, but this small cost can save you from bigger headaches down the line.

10. Take It to a Mechanic

No matter how thorough your personal inspection is, a professional mechanic’s evaluation is invaluable. They can identify hidden issues you might not spot yourself, such as internal engine trouble or transmission problems.