I wasn't planning to tow across country but I have several loads of
rock to haul 5 to 7 tons at a time. I have already made a dozen or more trips on the farm with 3 tons or more for testing and looking for weak spots in trucks operating system.
I did place a call to a local lab
"that I send my tractors used oils into for testing" to see what grade motor oil would be comparable to the original oil the motor was engineered for.
You are right the most expensive usually isn't always the best but I'm on my third oil change in a month and sending this one in to check for bearing and block wear .
