How Often Should You Change Your Oil?

maintenance required or oil change light
Time for an oil change!.

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You can find recommendations for how often you should change your oil in the owner's manual that came with your vehicle. This baseline number is a good place to start. However, your personal driving habits, as well as other factors like engine wear-and-tear, may mean that you need to change your vehicle's oil more frequently (or that you can extend the interval a little longer).

Check Owner’s Manual First

The main source for oil change information is the owner’s manual or maintenance manual. If you don’t have one, consult your dealer or look online. The owner's manual will provide engine oil recommendations for your vehicle's specific year, make, model, and engine. Oil type, viscosity (weight), and capacity are just as important as the oil change interval, so be sure to use a compatible oil.

Today’s automakers usually specify different oil change intervals for “normal operating conditions” and “special operating conditions” (sometimes called “severe service conditions”). Normal driving conditions refers to national averages: 11,500 miles per year, 45% city driving and 55% highway driving, passengers and light cargo only. Severe service refers to drivers who spend the majority of their time in stop-and-go traffic, making short trips, or hauling heavy loads. Counterintuitively, more highways miles are actually better for the engine and transmission.

A car driven in normal driving conditions requires less maintenance. For this vehicle, the recommended oil change schedule might be every 7,500 miles or 10,000 miles. If driven in "severe" or "special" conditions, the recommended oil change schedule might be every 5,000 miles or 7,500 miles for the same vehicle.

Examine Your Driving and Vehicle

How and where you drive are just as important as what vehicle you drive and what type of oil you use. For example, driving in stop-and-go traffic can lead to overheating, oxidation, and deposits, and short trips don’t allow enough time and temperature to burn off water condensation, a natural result of combustion. If this sounds like your driving style, follow the severe service schedule and change your oil more frequently.

Conversely, if most of your driving takes place on the highway, your engine has plenty of time and temperature to burn off accumulated water. You can safely extend your oil change interval.

Synthetic oil tends to last longer than conventional oil because it has fewer impurities. If you use synthetic oil, you can follow the normal service schedule and change your oil less frequently.

Engine problems can shorten the life of the engine oil. Worn seals and piston rings can increase oil consumption, leaving less oil to run the engine. Overheating can oxidize oil faster and lead to deposits. Cylinder misfires can lead to oil thinning, reducing its effectiveness as a lubricant. If you've experienced these engine problems, you should change your oil more often and get the engine repaired.

The Importance of Oil Changes

Engine oil is a lubricant, coolant, and hydraulic fluid. It's important for the function and longevity of your engine. All engine oils wear out over time, reducing the level of protection they provide, which is why they need to be changed regularly. A fresh charge of engine oil and a new oil filter restores free-flowing lubrication and piston cooling, extending the life of your engine.

Remember, all engines consume oil and many engines leak, so you should check and adjust the engine oil level regularly. Checking your oil every 1,000 miles only takes a few minutes and a rag. Every owner’s manual shows you how to do it, but if you aren't sure, ask a trusted technician for assistance. Carry extra oil and a funnel to top it off if the oil level goes below the “Low” marker.