I have a friend who is considering running either mobil delvac 1300 or chevron delo 400 in his VW. The question we are considering is that both are 15w40 oils and we are concearned they will be too thick for Northern Ohio winters. It can get down to around 0 degrees in the winter. Now the Delo has a pour point of -38 which is lower than many dino 5w30 oils so my gut instinct says it could be run in the winter, also the mobil I believe is -31 so it would seem like a viable option as well. The only synthetic diesel oil available here is Rotella T and he would rather not run the rotella, or pay the price for synthetic. Anyone run either of these 2 talked about oils in the winter before please post your findings : )