Conventional wisdom tells us that our cars need an oil change every 3,000 miles, and this was true of most cars at one time. However, with changes in engine design and the emergence of modern lubricants, it is not unusual for a car to go much longer before needing an oil change, depending on several factors.
No matter the vehicle, the interval between oil changes depends on the car's age, the type of oil used, and the driving conditions that the vehicle regularly undergoes.
Here's what all car owners need to know about oil change intervals so that you can be sure your car gets the TLC it needs to run its best.
Oil Changes for Newer Cars
Newer cars generally have longer oil change intervals than older cars. That's due to their use of synthetic motor oil, multi-grade, low-viscosity, and other newer generation resource-conserving motor oils that maximize a car's fuel economy and minimize friction. They're formulated to last longer before viscosity breakdown than old-school 10W30, 10W40 conventional oil, and so on, thus their longer service life.
Your owner's manual generally mentions the number of miles you can drive your late model car and the expected oil life for your new vehicle. These figures can vary widely. For example, Toyota Camry models with the 2.5-liter 4-cylinder generally go 10,000 miles between oil changes. BMW cars that use synthetic oil can go up to 15,000 miles. New car oil changes require that the right oil is used, based on the model and make of the car; it must be the correct SAE viscosity grade and automaker's recommendations.
Oil Changes for Older Cars
The old standby 3,000-mile oil change rule was a typical recommendation years ago when oil change intervals were based mainly on miles driven. But recommendations change.
On older cars from 2007 and earlier driven under typical conditions, most experts now recommend changing the oil every six months or 5,000 miles, whichever occurs first. Typically, an older car has two maintenance schedules: Vehicles driven under normal conditions and vehicles used in more extreme conditions.
Severe driving habits include being driven primarily for short trips of 5 miles or less, operated mainly in stop-and-go situations, towing a trailer or carrying heavy loads, or driving in a highly dusty climate, hot or cold. If you frequently drive your car under severe service conditions, you will need to go by the standard rule of changing the oil every three months or 3,000 miles. The owner's manual for your older car will help you determine the best oil change interval and engine oil type for your particular vehicle.
Oil Life Monitors
If your vehicle has an oil life monitor, it's easy to determine when your car is due for an oil change. These monitors come on most General Motors and Ford vehicles and base recommendations on criteria such as the number of cold starts, climate conditions, engine temperatures, and vehicle speed.
However, some owners of vehicles equipped with such monitors have indicated that their vehicle monitors sometimes suggest that they can safely drive even more miles past the recommended intervals for changing the oil.
Why Do Oil Changes Matter?
The significance of oil can't be underestimated.
Just like the blood that runs through a body, the oil in your car has many vital jobs. Oil cools and lubricates the hundreds of moving parts that keep your vehicle in good running shape. It protects the car's engine, preventing contaminants and dirt from forming sludge that can cause engine wear, potential damage, and reduced performance. It seals off gaps, reducing contamination by unburned fuel and water. Oil also prevents corrosion due to acid or moisture that might otherwise make its way into your car's engine.
Due to the constant work that motor oil does in your engine, it gets dirty. Moreover, once motor oil is "spent," the additives in the oil that power its magical ability to keep your motor running nicely become depleted. These additives include anti-wear agents that form a protective coating with metal surfaces to protect the life of your engine.
Detergents that reduce the formation of contaminants and inhibitors that prevent corrosion and rust from forming are also depleted. It can lead to your vehicle experiencing breakdowns in the components of the engine. The oil's friction modifiers also become depleted over time, which results in reduced fuel economy. And last but not least, viscosity index improvers in the oil are reduced, resulting in thicker oil that doesn't do its job as efficiently.
'But My Quick-Lube Guy Recommends It'
Well, of course, they do!
Some mechanics may still stick wholeheartedly to the old recommendation of changing oil every 3,000 miles. However, they may also do a good job convincing you that your car needs these frequent oil changes to avoid engine damage. It is, after all, in his best interest to replace the oil and oil filter at any chosen mile interval you'd like.
But consider that your best resource for determining how often to change your oil is the vehicle's manufacturer. The manufacturer's recommendations should trump those of the mechanic at your local service center.
Owners of older vehicles should maintain a regular regime of checking their oil. Whether you change your own oil or take it to the dealership for service, there is an easy DIY you can do to extend your vehicle's engine life. Checking the oil in your car is easy and can prevent big problems before they happen. Checking your oil once a month is a good habit to form.
The owner's manual should describe the process, but it is usually as easy as popping the hood and pulling out the dipstick. Grab a rag or paper towel to wipe off the initial oil, reinsert the dipstick, and remove it again. Look at the oil level compared to the etched lines or holes, and verify you have the appropriate amount. If the engine oil is low, top it off a little at a time, checking the dipstick until it is back at the right level.
If your vehicle regularly needs additional oil, it may be a sign of a significant issue. Newer cars are less likely to burn oil, so you may be able to go between oil changes without checking your oil, as long as you stick to the recommended schedule. However, it won't hurt to check the oil following the guidelines in your owner's manual for the nervous types out there, and even modern engines will suffer severe damage if they run dry.
The Bottom Line
Not all cars need to have their oil changed every 3,000 miles, and most carmakers agree, according to research conducted by Edmunds.com. Automakers are now recommending, for the most part, that cars have an oil change between 7,500 miles and 10,000 miles. Although you can't harm your car by giving it a fresh oil change before it needs one, it can be a waste of money. It is also bad for the environment since that old oil has to be disposed of and recycled.
Still, if you're a staunch believer infrequent oil changes, then the thought of driving your car for 15,000 miles without one may not sit well with you. But perhaps there is a middle ground. Some experts say to have your oil changed whenever you take your car in for a tire rotation. That gives you a chance to do both at once while having peace of mind that you're giving your car's engine the lifeblood it needs to be at its best.