[Hummie2]

Definitely believe in oil analysis. Used it for years in fleet service. You can be warned of problems that you would never have known about until it was too late and the damage was done. I remeber a few rigs that had very small leaks in the air intakes, they showed high silica in the anaylsis. We would never have looked for the problem or found them until the ring and cylinders were worn out if not for anaylsis. We never changed oil until the anaylsis said to. Usually that was well beyond 12months, we sampled the oil every 90 days and changed filters @180 days. It also helped us decide if synthetic was right for that fleet. It wasn't.