Well the Air Force has put me in the coldest damn place I have ever lived lol. I am getting ready to change the oil in my 2003 Explorer Limited with a 4.6l. I always use Mobil1 Synthetic of course but am not sure about the weight I should use. Most locals seem to say 10w30 if using syn and 5w30 if using conventional . What's your advice? The temp here has been staying around 15 below zero (fer) . But sometimes it has gotten as low as -50 and stayed for a a day or two. Of course I have a block heater and all but some places you can't plug in to keep the oil from freezing up and dry starting really bad. Also have to leave the thing idle alot when you go in somewhere so sometimes I have to keep it idle for 30 minutes or so. But anyway, any suggestions would be great and it's great to see everyone again. I hope by this summer I can pay off some bills and get another Mustang so wish me luck finding one here