[bestgenman]

Steve,  I’ve been using the LF9620 for several years with synthetic oil and the yearly test results look great.  I’m nearly 10,000 miles since last change and the reports are to continue with current operation.  Another one of our group, @Pardue101, is more knowledgeable on the series 60 since he is running them in his fleet.

10,000 miles would make non-synthetic oil ready for a change but with the synthetic, sampling, and the combo filter, the change interval can really be extended.