Oil Change - When?

[coopns]

One car which doesn't get many miles, all in town for the kids. Other is generator which I run 1 a month for 1/2hr.

Should I change the oil regardless of how little time in use - does oil lose its potency?

 

[AutoMechanic]

Depends on how many miles. Maybe every 6 months or year.

 

[simple_gifts]

Some specifics would be good, what car and engine? What is "doesn't get many miles?" For some that is 6K-8K year; I generally do yearly OC in the summer for my lightly used truck. This time around it is going to be 2 year OC. Oil doesn't "go bad" in the pan.

 

[rob1715]

+1. Define "doesn't get many miles".

 

[FordMan59]

If the car is driven enough each time or nearly every time it's run to get up to full operating temperature where it would burn off any moisture in the oil I see no reason to change it until it's recommended OCI. As long as the oil is just sitting in the oil pan I don't worry about it. I've got a '97 Ford that I use mainly for longer trips, I bought it new in Feb. '98 it currently has 41K original miles on it and gets an oil change every 5K miles regardless of whether the oil has been in it a year or 10 years. As for your generator if you're running it 30 minutes at a time that's plenty long enough to burn off any moisture in the oil. The oil I'm using in my cars has been in my garage for anywhere from about 15-25 years. I see no difference in the oil sitting on a shelf in a plastic bottle and sitting unused in the oil pan.

 

[Ram02]

1yr or every 20k whichever comes first using M1 EP

 

[DGXR]

Sounds like a short-tripper. What does your owner's manual say for your type of usage? That's a very good starting point.
Without a manual, I would default to annual service with the car. The generator sounds like it gets run long enough (gets hot enough) that you could probably go a couple years with quality oil.

 

[joekingcorvette]

I would change it once a year even if you don't drive it very often.