The longer it's been since your last oil change, the darker the oil will be.
If you don't want to adhere to a scheduled change at a regular interval, you
might decide what darkness of oil you can tolerate. The more wear you have
on your piston rings and cylinders, the faster gases will contaminate the
There was a recent discussion about frequency of oil changes on NPR's weekly
Car Talk radio program on car maintenance. The "Tappet Brothers" said more
and more car mfrs. will advise oil changes at intervals as far apart as
every 7,500 miles and use the relative infrequency as a selling point for
their vehicle. In response to this caller's questions, they recommended
every 5,000 miles.
About 10 years ago, with a non-Toyota, I deviated from my usual oil change
interval of 4000-5000 miles and went about 7900 miles before changing oil. I
believe a noticeable though not drastic dropoff in engine power dated from
that delayed change.
Someone told me years ago that for longer engine life, on a brand new car,
it's a good idea to get the first oil change at about 1,500 miles. His
reasoning is that because the castings from which engines are made are
always imperfect, you pick up a lot of very fine metal shavings at this
time, and by eliminating them very early in the engine's life, you maintain
better engine compression and power. That sounds logical to me.
Bill < firstname.lastname@example.org> wrote in message
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