Never needs an Oil change!
Heard this interesting theory from a local guy the other day. He never changes the oil in his Diesel Pusher BECAUSE he has to add a quart of oil every 1,000 miles. His theory is the oil is already c...
Forum Discussion
wny_pat wrote:I assume you are joking, as most of the actual engine oil is recycled. The interval cycle is really around 6K miles, and is based on a high capacity pan, and the rate at which ZDDP and other additives are used up. ZDDP is the governing factor, as the concentration of ZDDP is a rather narrow spec. Too much ruins the catalytic converter, too little results in excessive scoring. So the high capacity pan keeps the concentration level more consistent throughout the change interval. ZDDP is the determining factor, with other additives added based on the ZDDP change interval.
It has been ingrained into us that we have to change our engine oil every 3000 miles. The engine manufacturers have changed their requirements several years ago. The local Ford dealer is still telling me 3000 miles even though the book says 7500 oil change interval. No wonder we're running out of oil!!!
