thanks higgy.

One more additional thing in passing

Big diesle engines these days use what is called a bypass filter. There are engines in use with a million miles of heavy duty service and have never had their oil changed. They are now using them on motorcycles as well






Almost any heavy equipment service center can do the required testing to extend the time between oil changes for under 20 bucks USD

Amsoil 20W-50 in Paso and LC4.

I've used Amsoil almost exclusively in everything mechanical since around 1976 when introduced to it (the days it came in metal cans). Being minutes from a regional warehouse helps.