Late Model Vs. High Mileage Used Cars

When choosing a car, you may face a decision between a late-model vehicle and one with high mileage. It's usually easier to obtain a warranty on a late-model car, but high mileage vehicles are often less expensive per mile to operate if you do most of your own mechanical work.

Engine condition

Vehicles with high mileage often have lower engine compression than their late model counterparts. You notice the lack of power or a knock when accelerating. An oil additive with Teflon can be used to combat low compression. High mileage vehicles often require higher octane gas for the same reason.

Maintenance

High mileage cars usually require more maintenance than late model vehicles. You can expect to more frequently change the spark plugs, spark plug wires and fuel filter. You can expect to add anti-freeze fluid, brake fluid, and possibly transmission fluid more often if leaks develop. You'll need to adjust the alternator belt more frequently and check for bad electrical connections. Your idle speed may vary, and that requires adjustment or troubleshooting. Older parts require replacement.

Tires

High mileage cars often use tires much faster because tire alignment is costly and difficult. Rust and mud develop on wheel assembly components. The cost of repair can be more than the value of the car itself, so the alternative is to drive the vehicle, switch to less expensive tires, and replace them more often.

Ignition

High mileage cars are usually slower to crank than late model vehicles. The ignition system includes the battery, the starter, the ignition assembly itself, the distributor, the spark plug wires, the spark plugs and all of the wiring that connects the components. It sometimes includes an ignition module and a small starter solenoid. Cranking the car causes wear on the ignition system. Low engine compression and low fuel pressure may also be a problem for high mileage vehicles.

Overheating

According to Doug Newcomb of MSN Autos, keeping your engine cool is a critical part of saving money and extending the life of your car. Even replacing the cooling system components, having the system flushed by a professional, and changing the radiator fluid may an overheating problem. The problem is material buildup inside engine components, which raises the operating temperature. It's often a persistent problem, and during the summer months overheating can destroy the engine. This issue may not be apparent if you buy the vehicle during cooler weather.