Oil Change Interval for Low Mileage Use?

[Drew99GT]

I'm surprised someone would actually believe that B.S. and not use common sense and change the oil appropriately!

If your going for 200+K, change it more often; not at ridiculous amounts, but NOT AFTER 5 YEARS!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

If your gonna sell it after 5 years, OK, whatever...

 

[cheetahdriver]

well, if you don't believe it, lets see a peer reviewed paper in SAE proving it wrong....

however, if you read the whole thing you see a couple of items.

1) while the test was for 5 years, it's to show the oil will work fine, not longevity of the engine. however, the engine longevity was not compromised during the test. moreover, these cars were on a short cycle test to prove that synthetics can handle this sort of driving better than regular oils. nothing says that if at 60 months, if you took this car on a 90MPH drive cross country, you might not even make it out of the state.

2)the major point which most miss, is that while the oil wasn't changed, it was made up from the testing pulls. in fact, over the course of the 5 years, 4.4L of new oil was put in the car, and the car was a qt low at the finish, making the oil add effect even more pronounced. many tests show that even a small amount of make up oil has a great effect on the aggregate oil characteristics. these tests basically put a whole new oilchange in the car.

3) nowhere (that i found) did they say how many miles were put on the car. if you figure the cycle was done twice a day on weekdays only (9miles/day x 5 days/week x 52weeks/year x5years/test) gets you under 12k miles for the entire test. 12k miles for a synthetic is well within the usage parameters.

would i run 5 years on an oil? no way. do i believe the test? absolutely, but i also read the fine print (and put it in my post) that shows that the test isn't as great (or as bad) as it seems at first blush. my point is that for OCI's of 1 year or 10-15k miles (whichever comes first) the trip profile is immaterial. run the whole 15k at 90mph at one setting or do it 1 mile per trip, a good synthetic just doesn't care.

 

[Drew99GT]

I disagree. I recently changed my brother's oil which had about 1,500 miles and roughly a year. It came out black as tar with obvious moisture and smelled like a gas pump. He ONLY drives back and forth to work which is about a mile away; and to the grocery store and other small errands that are half that.

The oil might not care, but the metal in the engine will. Water + fuel/combustion byproducts at elevated levels = acid and corrosion.

 

[BarkerMan]

Talk about break in oil is confusing. I did a uoa on a Honda and found a boat load of moly in the oil that was changed out at 1k miles. I did a oua at 1k miles on the new oil and 2k on the engine and found the same boat load of molly in the oil. I have VOA info on the oil and there is not that much in there, not even close. Could it be that the oil gets a boost in moly from left over’s in assembly process? We also found silica in the first 1k oil sample that the lab said were very small particles that are difficult to detect. The amount dropped a bit at 2k and then disappeared by 5k miles. Could it be that it's useful to do an early oil change to flush out things, things that may not even be detected by standard production lab tests as applied to oil samples? I know that silicon combined with O2 is an antifoam agent and silica is used as a thickening agent in fip (formed in place) gaskets but I'd like to get as much out of the system as I could. I did an unscientific (no flames please) test of the silica (free silicone) in the 1k engine miles sample. I put a drop of oil between two microscope slides and slid them back and forth with as much pressure as I could apply with my finger and thumb. Under the microscope there were tiny scratches. I did the same test with new oil and no scratches. I would say that if you did this test on your new car and found any scratches that you should consider changing the oil. I do not believe there is any such thing as break in oil in modern engines. By the way you may need a microscope or at least a powerful macro lens to see the scratches. After seeing this test we started doing it on farm tractors and use it to determine when to change the air filter. Please, again, no flames, I’m not a chemical engineer.

 

[bmwtechguy]

Several years ago I met a retired Mobil corporate rep, and as our conversation turned to oil and synthetics and intervals, he stressed what he has told people for years, change your oil more often for the short trip crowd. For longer daily trips, less often is ok. Short trippers should change theirs based on time more so than on mileage. Also, I had friend with a Dodge Ram pick-up truck (gasser)with a bypass filter installed. He was thinking that he would be able to really extend his oil changes using the bypass and synthetic oil. He had his oil tested after a year and it was totally depleted (TBN) and had about 12k miles on it. He lived within walking distance of the hospital that he was working at every day, so that all those short trips added up prematurely contaminated oil. He had several long trips throughout the year as well. Maybe he would have been better off to forget about the bypass and just change his oil a few times a year with regular oil. He sold the truck later and left the bypass on it.

For the OP, I would have to agree with several on here that, based on your driving, the oil you have in there should be ok for up to one year, longer if you want to test it.

 

[BarkerMan]

For owners that keep their cars or short run drivers the problem is corrosion, not wear. Wear has been pretty much handled with modern engine design and oil improvements. Oil changes should be based on avoiding corrosion.

 

[jorton]

Originally Posted By: nick778
My question is do I change it before winter due to i.e. built up acids in the oil and such or is it fine for another 3-4 months?

Of course my oil meter in the car says I still have 70% usage left on the oil.
Thanks.


I think now is too soon to change and I'd wait for 30/40% usage left for a conservative oci.