I've always ignored the 3,000 mile/3 month recommendation that these places
tell you. I figure that just means more money for them, I do it on average
between 5-6k miles, never had any problems...
I don't know... I think the auto manufacturers want you to change it less
often so the engine wears out sooner. This is a conspiracy.
If you are concerned one way or the other a simple oil analysis will tell you
for sure and you will not need to worry anymore.
Old habits are hard to break. Years ago, when engines were less sophisticated
and wore out sooner, 3000 miles was reasonable. Nowadays, engines and oils have
been improved tremendously. The comment about auto manufacturers wanting engines
to wear out sooner is foolish. First, one of the big sellinig points of a car is
its reliability and durability, how long it lasts. Secondly, the vast majority
of people buy new (or newer) cars because they want change--something newer with
the latest gadets, not because their cars wore out. @Hoopty6: what
is a simple oil analysis? Who does it and for how much? Unless it were done for
free, it seems rather pointless.
What is needed is an inexpensive and convenient test to determine the health of
a cars motor oil. Even better would be a sensor so the car could