I was wondering if a 15w40 oil is too thick for the v6 in my Honda Ridgeline and the inline 4 cylinder in my wifes Neon? I work at a truck repair shop and can get a good price on Delvac 1300 of $1.50 per quart from our bulk tank. I live in Ohio so they see all kinds of temperatures. Thats all we run in the shop vehicles from the forklifts, air compressors, Impalas and S-10 trucks, ect with no problems, but I dont want to damage my stuff in anyway. Whats everybodies opinion?