How often should you change your oil?

The old 3,000 km (or 3-month) rule is a holdover from decades ago, kept alive mostly by shops that profit from frequent changes. Modern engines and modern oils are far better than that. The correct starting point is always your manufacturer's recommended interval, which you'll find in the owner's manual or the car's maintenance schedule.

For many modern vehicles on full synthetic, that's somewhere in the range of 8,000 to 12,000 km, and some go further. Your car may also have an oil-life monitor that estimates when the oil is actually worn based on how you drive — a better guide than a fixed number for a lot of people.

Yes, and in Calgary especially. Synthetic oil flows much better when it's cold, which means faster lubrication on those brutal winter start-ups when most engine wear happens. It also resists breaking down under heat and holds its protective properties longer, which is what allows the longer intervals in the first place.

Most vehicles built in the last decade or so specify synthetic, and many require it — using conventional oil in an engine designed for synthetic can cause problems and may even affect your warranty. If your car calls for synthetic, use synthetic; the extra cost per change is more than offset by longer intervals and better protection.

Here's the part most people miss. Those longer intervals assume 'normal' driving — steady highway kilometres that let the engine run hot and burn off moisture and fuel that sneak into the oil. A lot of Calgary driving is the opposite: short trips across town, frequent cold starts, stop-and-go, and long periods of extreme cold.

Manufacturers call that 'severe service', and it has its own, shorter interval in the same manual. If your typical day is a few short, cold hops rather than a long commute, you're likely in the severe-service category and should change oil more often than the headline number — closer to the shorter figure in your schedule.

Oil doesn't fail all at once, which is why skipping changes feels harmless — right up until it isn't. Over time, oil thickens with contaminants, loses its additives, and stops protecting and cleaning the way it should. The result is accelerated wear, sludge build-up that can block oil passages, and on some engines a real risk of expensive internal damage.

An oil change is one of the cheapest things you'll ever do for your engine, and one of the most consequential. Chronic neglect is a leading cause of the big-ticket engine failures we see.

A proper oil service isn't only draining and refilling. The oil filter should be replaced every time, and a good shop uses it as a chance to put the car on a hoist and look it over — tire condition, brakes, leaks, suspension, fluid levels. That quick check is often where a developing problem gets caught early, while it's still cheap to fix.

It's also why a dirt-cheap quick-lube isn't always the bargain it looks like: you may save a few dollars on the change and miss the look-over that would have saved you a few hundred later.

Use the manufacturer's interval as your baseline, use the synthetic grade your car specifies, and shift toward the severe-service interval if your driving is mostly short, cold trips — which, in Calgary, it often is. If you're not sure which category you're in or what your car needs, ask us and we'll give you a straight recommendation based on your specific vehicle and how you drive.