How often do I need to have the oil changed in my car?

[Anonymous]

A 2018 Mazda cx5? (I’ve heard different recommendations)

[Anonymous]

What does your owner's manual say? If you don't have a physical copy I'm sure you can find it online. My cars have always been 3,000 miles but I don't know if that's true for all cars.

[Anonymous]

Depends on your driving style. If you drive lots of short trips of less than 30 minutes, you need to change your oil at a maximum of 3,000 miles or every 12 months regardless of mileage on the oil. This is because short trip driving quickly accumulates unburned fuel in the oil, and since the engine never gets hot enough for that fuel contamination to “boil” out of the oil, it stays in the oil, where it can damage and wear plastic and rubber components in your engine (cam chain guides in particular).

If you drive more than 30 minutes for most trips, you can probably do a longer oil change interval, up to around 7,500 miles if you’re using synthetic oils.

Some oil manufacturers claim you can go much longer (20k miles!) but I’ve never considered that smart or safe for your engine.

In the end, always remember this:

“Grease is always cheaper than metal”.

[Anonymous]

Mine are both every six months or 5,000 miles, whichever comes first. Truck is 3,000 miles with regular towing and/or driving on dusty dirt roads.

I read an article once, written by a recently retired Exxon petroleum engineer who explained advances in motor oil formulation were such that doing anything more than the manufacturer's recommendation does nothing for your car, but does contribute to his pension fund.

Find your manual as noted above.

[Anonymous]

Adhere to the recommendation in the owner's manual. It is based on what the people who built the car know. Sometimes dealerships and even independent shops will suggest shorter intervals, but that's usually not necessary and is a way to increase dealer/service center profit.

If you want to maximize engine longevity and the car uses conventional oil, the owner's manual will probably tell you to change it with the oil filter every 5 - 6K miles. Some people choose 3K intervals to be extra-conservative.

If the car uses synthetic oil, intervals will be longer.

If you do a lot of short trips which don't allow the engine to fully warm up, shorter intervals are prudent as condensation can form which is not burned off due to low engine oil temps. Similarly, shorter intervals may be recommended if you do a lot of stop-and-go driving which is harder on the engine, e.g., Uber or Doordash driver, or someone who mostly drives in an urban environment.

If you drive a EV, no oil or oil filter changes at all!

[Anonymous]

Anonymous wrote:Adhere to the recommendation in the owner's manual. It is based on what the people who built the car know. Sometimes dealerships and even independent shops will suggest shorter intervals, but that's usually not necessary and is a way to increase dealer/service center profit.

If you want to maximize engine longevity and the car uses conventional oil, the owner's manual will probably tell you to change it with the oil filter every 5 - 6K miles. Some people choose 3K intervals to be extra-conservative.

If the car uses synthetic oil, intervals will be longer.

If you do a lot of short trips which don't allow the engine to fully warm up, shorter intervals are prudent as condensation can form which is not burned off due to low engine oil temps. Similarly, shorter intervals may be recommended if you do a lot of stop-and-go driving which is harder on the engine, e.g., Uber or Doordash driver, or someone who mostly drives in an urban environment.

If you drive a EV, no oil or oil filter changes at all!

There are definitely fluid and lube services required on most EV’s.

[Anonymous]

Anonymous wrote:

If you drive a EV, no oil or oil filter changes at all!

There are definitely fluid and lube services required on most EV’s.

"Oil and oil filter" pretty obviously refer to engine/motor oil, not to lubricants for door hinges and the like. Vehicles without internal combustion engines (ICE) use neither motor oil nor oil filters. They may require transmission/transaxle or other fluid exchanges, but those change intervals will be much less frequent than the oil/filter changes required of internal combusion engines. No radiator fluid replacements will be required, either, since no engine cooling system using a fluid-filled radiator is present on EVs.

Routine maintenance for EVs is largely confined to occasionally replacing tires, windshield wipers, brake pads and possibly rotors, and cabin air filters, and eventual replacement of the battery. None of the maintenance associated with ICEs is required, i.e., spark plugs, engine oil, engine oil filter, air filter, radiator coolant, and radiator hoses.

[Anonymous]

Anonymous wrote:Mine are both every six months or 5,000 miles, whichever comes first. Truck is 3,000 miles with regular towing and/or driving on dusty dirt roads.

I read an article once, written by a recently retired Exxon petroleum engineer who explained advances in motor oil formulation were such that doing anything more than the manufacturer's recommendation does nothing for your car, but does contribute to his pension fund.

Find your manual as noted above.

At least every 5,000 miles. You don't want oil passages to get blocked. Don't care what the oil service light says.

European cars will often say 10K or more for the "Umwelt" because they include oil changes in the initial cost of buying the car and it's out of their pocket to change the oil for the first several years.

When you start getting a quiet ticking, it's because you followed their recommendation, the oil passages get plugged up and the valve lifters get worn out. It gets worse with time.

[Anonymous]

I have a 2018 Honda CRV. Every 5,000 miles.

[Anonymous]

Doesn't your manual or the car itself tell you when you need a service?

[Anonymous]

Anonymous wrote:

Anonymous wrote:Mine are both every six months or 5,000 miles, whichever comes first. Truck is 3,000 miles with regular towing and/or driving on dusty dirt roads.

I read an article once, written by a recently retired Exxon petroleum engineer who explained advances in motor oil formulation were such that doing anything more than the manufacturer's recommendation does nothing for your car, but does contribute to his pension fund.

Find your manual as noted above.

At least every 5,000 miles. You don't want oil passages to get blocked. Don't care what the oil service light says.

European cars will often say 10K or more for the "Umwelt" because they include oil changes in the initial cost of buying the car and it's out of their pocket to change the oil for the first several years.

When you start getting a quiet ticking, it's because you followed their recommendation, the oil passages get plugged up and the valve lifters get worn out. It gets worse with time.

Yep!!!!!

That little tick-tick-tick-tick-tick…. Like a stopwatch.

Ticking off the weeks/months until your valves start contacting the tops of the pistons, and your engine destroys itself.


But hey, you saved like $300 by doing fewer oil changes, so that totally offsets a new engine

[Anonymous]

10,000 miles w synthetic. Changing every 3000 is bs just to line the pockets of mechanics with easy cash.

[Anonymous]

Anonymous wrote:10,000 miles w synthetic. Changing every 3000 is bs just to line the pockets of mechanics with easy cash.

I have a 2020 forestor that I got new just before the pandemic. I also wfh and mostly do short trips. I think I have changed the oil like 4x since I bought it. Synthetic oil. Car has like 25K miles.

[Anonymous]

Anonymous wrote:10,000 miles w synthetic. Changing every 3000 is bs just to line the pockets of mechanics with easy cash.

If an engine sees almost exclusively highway use, I might consider going to a 10k/mi interval, but ONLY after having used oil from that vehicle lab analyzed, and making absolutely sure I stayed with the same brand and grade/weight oil. Ideally down to the same lot number, which would necessitate buying a substantial amount of oil in advance.


But every customer’s engine I’ve ever torn down after a failure has shown evidence of both oil contamination and oil sludging, from short trip driving and longer than recommended change intervals. In DOHC engines with variable valve timing, the oil sludging is particularly dangerous, because the lifters and valve trains are controlled by oil pressure, and the actuators have tiny oil passages that are easily blocked by sludge from old oil.



Do what you want…. But I make wayyyyyyyyy more money putting in remanufactured engines or cylinder heads than I do on oil changes.

Your choice.

[Anonymous]

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:Mine are both every six months or 5,000 miles, whichever comes first. Truck is 3,000 miles with regular towing and/or driving on dusty dirt roads.

I read an article once, written by a recently retired Exxon petroleum engineer who explained advances in motor oil formulation were such that doing anything more than the manufacturer's recommendation does nothing for your car, but does contribute to his pension fund.

Find your manual as noted above.

At least every 5,000 miles. You don't want oil passages to get blocked. Don't care what the oil service light says.

European cars will often say 10K or more for the "Umwelt" because they include oil changes in the initial cost of buying the car and it's out of their pocket to change the oil for the first several years.

When you start getting a quiet ticking, it's because you followed their recommendation, the oil passages get plugged up and the valve lifters get worn out. It gets worse with time.

Yep!!!!!

That little tick-tick-tick-tick-tick…. Like a stopwatch.

Ticking off the weeks/months until your valves start contacting the tops of the pistons, and your engine destroys itself.


But hey, you saved like $300 by doing fewer oil changes, so that totally offsets a new engine

Hm, my car is 11 years old, been parked outside most of its life, and I've changed the oil every 5000 miles which, for me, is about once a year. No new engine needed..