I have wanted to try Ow-40, but I have two major concerns. 1.) film stength once the oil gets 3000 miles + and 2.) Oil sleeping through the rings when the oil is cold.. After all, OW is freaking light.... Too light for those of us who drive very hard! I have been tempted to just screw it and run 15W-50 through my 1.8T. The only thing that holds be back is the cold viscosity. So, I was thinking if I mixed 0W-40 & 15W-50 50%/50% I'd eand up about a 7.5W-45. Sounds perfect to me! Very tough and probably long lasting. What do you guys think?