Oil changes, is it the date or the mileage that's more important to go by?

Question

I have a (nearly) 6-year-old Subaru Legacy, and I regularly have the oil changed. The garage where it's serviced puts a sticker on the window giving me the date and mileage the next oil change is due. I'm usually well past the date before the mileage catches up. For example, I hit the due date on the 3rd of this month, but I'm still just under 1,000 miles under the mileage they gave. So should I do it now or wait until it's closer to the mileage, or is it really not all that important?

I want to do my best to keep this car running for many years, as it's been an excellent car. For the record, it's been trouble-free when it comes to its internal parts and has never needed repairs.

Answer 1

Mileage is more important, however I would not go more than a year without changing the oil, regardless of the miles since the last oil change. I have an old F-150 that I might drive maybe 2000 miles a year. It gets it's oil changed every year. And my old Triumph which gets driven less than 1000 miles a year, gets it's oil changed annually as well.

Answer 2

Milage is more important but for normal driving conditions, change the oil every 3 months or 3 thousand miles, which ever comes first. (it's not a big deal if you go over a little, these are always recommendations, not exact numbers)



The oil's viscosity degrades and can cause poor lubrication. If you only drive 1k miles a year, at the very least, do 2 oil changes.

Answer 3

Change it when the mileage calls for it. The only time you worry about the date is a car that sits for a really long time without being drove. Oil changes are also more important during cold weather on cars that aren't driven long enough to thoroughly heat up the engine. In cold weather try to drive the car at least 20-30 minutes to burn off condensation in the engine.

Answer 4

Mileage if the car is regularly driven. But don't go by the garage. They'll tell customers to get a 3000 mile oil change even if you are using synthetic oil (which has about 2x-4x the duration).

Answer 5

Mileage

Answer 6

Miles, newer formulated oils don't absorb water like older style oil, Subaru's factory recommendation is still lower than most, so really you have no need to change the oil any more than tge recommended 3750 miles, they make no calendar recommendation.



Many car makers (Ford, VW, BMW, Honda) now recommend 12 months/10,000 miles, that seems a bit long, I change mine every 5000, which for me is about 6 months.

Answer 7

The mileage is the most important thing to go by. Motor oil is pretty stable stuff and does not absorb moisture so there is no good reason to change it based on the date unless t is REALLY old.

Answer 8

Both. Change your oil and filter, under normal driving conditions, every 4 to 5k miles or annually, which ever comes first. It's that easy.

Answer 9

If the car isn't driven regularly, the date is more important.

Answer 10

Just have it done twice a year, June and December..

Answer 11

which ever comes first.