I price it around, and this fall the best deal was at my local CaseIH dealer who had 15_40 in bulk. I took my old rotella barrel in there and he refilled it and slapped on a case oil sticker. I would be highly surprised if all this oil didn't come out of the same cooker. I have never noticed any change in performance, or anything else for that matter whatever the brand of motor oil. You run it, it gets dirty. For a motor that runs full rpm and mostly full power all the time like a combine, 150 hours is way too long for me. I will stick with 80. gs