[DaleRobertson]

Synthetic motor oils can be used to extend change intervals out past 20K miles. to do this safely you need to send oil samples in at pre determined intervals for a spectrum analysis. You give the lab the details of your vehicle and the type of oil along with a fresh sample of good oil that you will be using for a baseline. You will want to change oil filter based on regular intervals of approx. 7000 miles. You can install a full flow oil filter with an intergal by-pass filter to extend the filter life as well