How often should you really change your oil?

The Car Doc · Hot Springs, AR · 5 min read

“Every 3,000 miles” got drilled into all of us, and for a lot of modern cars it just isn’t true anymore. Change it too often and you’re wasting money; wait too long and you’re cooking your engine. Here’s how we’d tell you to think about it.

Start with your owner’s manual

The folks who built your engine tested it harder than any quick-lube sign ever will. Most cars built in the last 15 years call for somewhere between 5,000 and 7,500 miles on conventional oil, and many that use full synthetic can go 7,500 to 10,000. Find the maintenance section in your manual — or just ask us — and start there.

Then adjust for how you actually drive

Here’s the part the sticker on your windshield doesn’t know: most manuals have a “severe service” schedule, and a lot of us live in it without realizing. You’re in severe service if you do mostly:

• Short trips — under 10 miles, where the engine never fully warms up
• Lots of stop-and-go around town
• Towing, hauling, or running a loaded-down truck
• Dusty back roads, or long idling in the Arkansas heat

If that’s you, shave a couple thousand miles off the “normal” number.

Synthetic vs. conventional

Synthetic oil holds up better to heat and goes longer between changes. It costs more per jug, but you change it less often, so it often comes out about even — and it’s easier on the engine. If your car calls for synthetic, use synthetic; don’t try to save a few bucks going backward to conventional.

Don’t just watch the miles — watch the calendar

Oil breaks down sitting still, too. If you only put a few thousand miles a year on a vehicle, change the oil at least once a year regardless. That weekend cruiser in the garage still wants fresh oil every spring.

The bottom line

For most daily drivers: around 5,000 miles on conventional, 7,500 on synthetic, sooner if you run hard or short. Not sure what your car wants? Bring it by or give us a call — we’ll look it up and tell you straight.