I wouldn't worry. Do it every 6 months, just make sure you get the oil good and hot when you do drive the car and you will be fine.
does age affect synthetics (mobile 1) less than petro-based oils? I drive the 525 only on weekends...seems futile to change oil every 1000 miles, which is about what I do in 3 mos. can I go 6 months or more?
I wouldn't worry. Do it every 6 months, just make sure you get the oil good and hot when you do drive the car and you will be fine.
1992 535i TCD-s2
Here's a study on synthetic oil change intervals"
http://neptune.spacebears.com/cars/s.../oil-life.html
Ramon
1994 540iA Nikasil EAT Chip
Tampa Bay, Florida USA
a red flag for me is that the study uses low mileage cars. If they used synthetics in cars of 100k and even 150k+, I wonder what their results would be.
don't think it matter that much...downside of using higher mileage cars is they tend to consume more oil and hence would taint results because clean oil is added to the car's sump over time which reduces metal traces. For testing purposes, best to use an engine that does not consume much oil. Other thing is this study does not address the poster's initial question and that is the influence of time versus mileage. This study is performed within a relatively short time frame and does not speak to leaving synthetic in for a long period of time with low mileage use. I too face the same situation...long time period oil change intervals due to low mileage use.
George
Another consideration is that higher mileage cars tend to produce more blowby into the crankcase, therefore contaminating and diluting the oil faster.
I have been using mobile 1 in my last two 5ers.....both high mileage. I would't change the oil any sooner than 6 to 9 month depending on the time of year. The more stabile, drier and warmer the weather, the longer you can go.
Oh and that 0-40 Mobile 1 is all I use now.... If you hate your car use Pennzoil..
ditto...also shorter duration driving adds a lot of condensation to the oil resulting in need for more frequent change intervals. Not sure if Pennzoil is so bad for dino oil.
George/ Mobil 1 fan
General rule is change your oil at least once a year. Given you are only driving approximately 4000 miles a year, you may want to consider using dino oil changed once a year, barring you are running lapping days or driving the car in -20F weather. Chevron, Pennzoil (yes Pennzoil, the old sludge problems are history), and Castrol all make good mineral oils. Choose the appropriate weight for your temperatures based on the factory manual recommendations.Originally Posted by Unregistered
Cary
the people at bobistheoilguy.com have three favorite conventional cheap oils: pennzoil (despite what has been said about it in the past), chevron supreme, and castrol regular. i wouldn't believe the claims about pennzoil being a good oil until i had read some of the oil analyses over there done on pennzoil.
My point still stands. I understand you need lower mileage vehicles to get more reliable results; reduced contamination, oil consumption... but in our high mileage cars, the frequency of oil change would be higher than, say, a 30k mile car. So to answer the question in the original post, the age of oil would certainly depend on the mileage of the car. Whether you have synthetic or mineral-based oil, the same applies to both. Right?