Interesting story : Have been doing oil analysis on my almost 2 year old John Deere (still under warranty) with each oil change. Blackstone who does my tests, was concerned about some elevated levels. Contacted my dealer who went up the ladder in JD. Their engines are designed for industrial use first and marine use second. In agriculture, logging, and mining, these engines run at a much higher percentage of maximum output. Part of routine engine analysis and preventative maintenance is oil analysis. To that end JD has their own internal document for dealers regarding acceptable levels, elevated levels, and warning levels. The engine models are broken down into groups with similar wear numbers. My dealer is kind of old school and generally doesn't do oil analysis, so he just forwarded the document to me.
While I like the people at Blackstone and thick there lab work is good, having the manufacturer's recommended values gives a real baseline based on a lot of research.
The elevated numbers in my oil analysis are between 1/4 and 1/2 of what JD consider normal.
Ted
