Can motor oil expire? (chronologically)

Jasconius

I have a car that I do not drive much. I haven't had to change the oil in 11 months, and in that time I have driven the car only 2,500 miles.

Should I still get it changed just because it's been sitting for so long? Can oil expire? In subtropical temperatures if it matters.

Psychotic One

The seals and such can dry out if left off to an extended period of time. If you are running the car every few days it should be fine, but it couldn't hurt to get an oil and/or lube when you got some spare time.

I guess also is it natural or synthetic oil?

Midshipman

Oil does not expire (at least not short of centuries passing). Usually the need for an oil change is driven by the saturation of the filter. Don't worry, your car is fine.

wmelon

Motor oil doesn't really expire, but it will break down due to contaminations. When you take many short trips over that kind of time frame, you'll end up with condensation in your oil that isn't getting burned off and can lead to the oil becoming varnish or sludge in your engine.

So If you're not going to be driving much I'd recommend changing the oil at least every 6 months.

Cycophant

wmelon wrote: »

Motor oil doesn't really expire, but it will break down due to contaminations. When you take many short trips over that kind of time frame, you'll end up with condensation in your oil that isn't getting burned off and can lead to the oil becoming varnish or sludge in your engine.

So If you're not going to be driving much I'd recommend changing the oil at least every 6 months.

This.

Although 6 months seems a bit excessive to me. You'd just be wasting a lot of oil. Once a year seems like a reasonable frequency to me; it's what I usually end up changing my oil at, and I drive less miles a year than you do.

MushroomStick

You should run your car like once a week or so, at least when its going to sit for a while. The oil itself doesn't expire, as for the additives/detergents/etc. that's in the oil, that can be another story. When you run your car, check the dipstick, and if the oil looks dirty it needs to be changed.

Zeon

Oil sitting in an engine gets more acidic over time, both due to metals from the engine contaminating it and carbon from the combustion process. Thats why the oil change intervals are generally every 4000 miles OR every 6 months, which ever comes first.

Oil sitting in a plastic jug with a cap on will not expire though. Cap open, it will take in moisture and dust from the air.

wmelon

Cycophant wrote: »

wmelon wrote: »

Motor oil doesn't really expire, but it will break down due to contaminations. When you take many short trips over that kind of time frame, you'll end up with condensation in your oil that isn't getting burned off and can lead to the oil becoming varnish or sludge in your engine.

So If you're not going to be driving much I'd recommend changing the oil at least every 6 months.

This.

Although 6 months seems a bit excessive to me. You'd just be wasting a lot of oil. Once a year seems like a reasonable frequency to me; it's what I usually end up changing my oil at, and I drive less miles a year than you do.

I guess it really depends on your climate. It's extremely humid here (> 50% average). If you lived in death valley, I'm sure you'd get less contamination due to water.

THEPAIN73

CHANGE IT!!!

It can destroy your seals and your engine if you don't.

Source: I work for a dealership.