Hi, my name is Phil. I am new to this forum and the diesel truck thing in general. I finally made my first diesel purchase the other day. I picked up a 2006 F250 crew cab, long bed, lariat. I love the truck, but this morning when I got in my truck I noticed something that I thought was unusual. It was around 35 degrees outside and I started to drive to work. I turned on my heat and it was warm unusually fast, in a matter of less than 2 minutes. The strange part is, while I drove, my heat every minute would go cold for a few seconds and then back to warm until the engine temp came up and then it was constant heat the rest of my drive. Maybe this is normal in this type of truck, so I apologize in advance if it is a stupid question. Thank you for your help in advance.