Time vs miles

[KL2BE]

I have 4 vehicles that each accumulate about 2,000 miles a year ('06 Mazda MX5, '10 Mazda CX9, '93 Isuzu Trooper and '05 Subaru Outback). None qualify for "severe use"; vertually all the miles are on the highway on a warmed-up engine.
Seems like a waste of good oil to change at 12 months just because of time when the engine has clocked so few miles. 5 gallons of little used high quality oil to the waste-bin seems like a crying shame. Also a big expense to send 4 samples for annalysis to Blackstone.
Question 1: What happens to a high quality oil such as Mobil 1 or Shell T-6 after 12 months that renders it unfit even though it may have served for only 2,000 easy highway miles???
Question 2: what kind of engine damage might I expect from changing every 2 years at 4,000 miles??

 

[hhu168]

If I were you, I would:

1. Switch to the cheapest conventional oil I could find;
2. Stop doing yearly oil analysis, at least not on all 4 vehicles;
3. Consider selling one or two vehicles.

 

[CATERHAM]

1, The oil is not unfit for further service.

2, No engine damage whatsoever.

The only concern I would have in recommending a 2 or 3 year OCI is your climate and whether indeed you do get the engines fully up to temperature every time to run them.
The test would be if you ever see condensation under the oil cap' in the dead of winter after a run? If you don't then base your OCI on mileage alone or 3 years, whichever comes first.
Of course if any of your vehicles have a OCM, obviously you should follow that.

 

[yaris0128]

Time isnt worth considering in my book. As long as its not waaaay out there. The least you could do in super long OCI's time wise is replace the filter. If your OCD about it. Ive got 11 months on my current del sol Pennzoil Ultra 5w20 fill and it has BARELY over 4k on it. Im not willing to dump that oil just because it has reached the DOOMED year mark. It will survive the winter and then Ill change it in the spring. Ive got to get my money out of that $26 jug dont I?

 

[jorton]

Carefully monitor oil consumption. If you see an unexpected increase in consumption, that could indicate severe fuel dilution. At that point you would adjust OCI.

 

[MuzzleFlash40]

I've always done twice a year oil changes on my toys. I'm just to OCD to let it go any longer than that, lol.

 

[mechtech2]

1: Those oils should NOT be unfit after one year in your circumstances. I'd go 2 year OCIs and forget about it.

2: The only likely engine damage is from you stripping the drain plug.

 

[Bamaro]

Originally Posted By: CATERHAM
1, The oil is not unfit for further service.

2, No engine damage whatsoever.

The only concern I would have in recommending a 2 or 3 year OCI is your climate and whether indeed you do get the engines fully up to temperature every time to run them.
The test would be if you ever see condensation under the oil cap' in the dead of winter after a run? If you don't then base your OCI on mileage alone or 3 years, whichever comes first.
Of course if any of your vehicles have a OCM, obviously you should follow that.

Good answer. Waste of time, money and resources for yearly changes in your situation.