I have tough decision to make and would like your input.... I have two $10 Mobil 1 mail-in rebates and I don't know how to best use them. Here are the vehicles in my family.... 2007 Toyota 4-Runner (I am now using PP 5w30 in this rig) 2007 Toyota Yaris (It has been on M1 all along, but I have 4 quarts of Castrol Syntec waiting for it's next fill.) 2008 VW Rabbit (yeah, it takes 502 Castrol 5w40) 1989 Jeep Wrangler (It likes Mobil DELVAC 1300 15w40) 2007 Suzuki DL650 VStrom (It just got Amsoil Motorcycle) 2-Honda XL600 Enduros (They like DELVAC 15w40 like the Jeep) So, besides purchasing M1 and giving it too one of you beggars, what should I purchase and for which vehicle?????? I am toying with the idea of purchasing M1 Diesel 5w40 and using it in the Enduros. What do you think?