i had 14 degrees this morning at the shop,man is it getting cold fast.and we have already got a foot of snow.the high today is about 35 degrees with the sun out.if glow plugs dont work up here your truck dont start and somtimes because of being at 10000 feet above sea level when it gets real cold i dont care if you have the best glow plugs in the world your truck wont start not plugged in.