Re: 929 oil change intervals - Question
r1, totally disagree with the 8k oil change. from oil tests i have seen, the oils lubricating quality's hold up that long, but the build up of acids and other impurities from the combustion process contaminates the oil far earlier.
IMHO it is cheap insurance to change the oil every 3k, and i am on the line of bettingpython with being anal about changing it before a long ride than letting it go over in miles. i have always done the 3,000 oil/filter change since i had my first car, and all vehicles since, and have had high mileage with no engine failures, and also very minimum combustion loss, far below normal.
the proof is in the science. i feel you would be better off running cheap oil and changing it every 3,000 miles, than running $10 a liter oil and changing it every 8,000.
always change the oil filter and oil together, and for oil i like the castrol r4, but i also feel that any of the high grade synthetics are a good choice. do some searches on oil on this site and you will get more info than you know what to do with.