I'm using 20w50 VR-1 in my 440 and change it once a year because I'm only averaging around 2000 miles a year. I also use 10w30 VR-1 in my 383 stroker Corvette. I chose VR-1 after much debate but the zinc and the in block hydraulic flat tappet cams seemed like the only way to go. I have never saw 10w40 VR-1 on any shelves. I know lots of people who use the diesel oil in their gasoline engines and have no issues but I would never use it because those diesel engines operate at much lower rpm's and zinc is being reduced to almost nothing due to the EPA mandating the use of catalytic converters on diesel engines. Zinc stops catalytic convertors up is the reason for its reduction or elimination in oils.
