I bought this truck two years ago with 186,000 on it. I have been using Rotella 15w-40 ever since I bought it. We have a shop on the farm, with a hydraulic 2 post lift, so it's pretty easy to perform the basic maintenance.
SYN> I was going to use a 5W-40 that Maxtron makes but the store didnt have any in stock. Would have had to order it, so I took the 15w-40 they had.
I wonder what I should try for oil change intervals, since I am trying the synthetic? I took an oil sample of my old oil when I changed it this afternoon, so will send it in for analysis. It will be interesting to take another sample at my next oil change to see if the synthetic had any effect.