Hi fellas,
I knew a work colleague who changed the oil on his Corolla every 2K as a matter of course. Nothing retentive when you think of what it's got to do going though temperature extremes day in day out.
It's the bridge between a well running engine and self destruction. It's not hard to imagine a breakdown occurring on a molecular level.
The prescribed intervals are designed I think as the maximum tolerance to keep it realistic for the lowest common denominator to keep a minimum standard before destroying the motor.
This 15,000km bull-sugar the makers are peddling now is lunacy. I won't even run to my 1980s Laser's 7.5K Intervals. My latest one was 3K and the oil was already looking quite brown on the dipstick.
Oil is really like a vital mechanical part of the motor which must be replaced when it wears out.
