re w w or w zowie daedalus stanford edu craig powderkeg deforest writes if you re planning on making long drives the w is probably fine esp in the summer in your w car but if you re making short drives stick to the w several years ago gm was having trouble with the rings sticking on the diesel they traced a cause to the use of w oil they would not honor warranty work if w was used if my memory serves me or was ok d though mark b
