Oh, let me clarify. The idea of oil testing has been thrown around a lot when discussing oil change intervals. My point is that you are trying to protect a $1500 investment. Who the f$% cares?

Now if you have a $50k engine, oil testing makes sense. And, why wouldn't you just change the oil if oil testing costs you $20? It just doesn't make any sense to me.

Therefore, I am doing a real life test with the method I recommend. Use synthetic diesel oil, change the filter once per year, top off as necessary.

That's it. Very simple. If one of the engines blows up, I was wrong. If nothing happens, I was correct. I don't want to complicate it any more than it has to be.

Yes, it's a sample of two. If others would like to join in, they are free to do what they will with their cars.

240Joe