I need some help. I have a 2001 24v 3500 ram 2wd with a 5 speed manual. When the temps get below 40*F it will not start. I have tried cycling the heaters multiple times, new batteries, new lift pump, and still nothing. When I plug the truck in at night, it starts fine. Once I get it started when its cold, it will start up fine unless it sits and cools off to air temps below 40*. The other day, the same problem, and the batteries ran down trying to start it. I didnt have it plugged in. So my dad and I tried to pull start it. As soon as I let off the clutch in 3rd it fired right up. The truck runs great and has plenty of power. My fuel pressure with a FASS DDRP is 15 psi at idle and 10-13 WOT. I have checked for air leaks but cannot find any. Keep in mind this is not a problem when its above 50 degrees. I had the codes read at Autozone and nothing showed up. The fuel heater and air heater test out fine. The other day I used the wifes hair dryer in the air breather to supply hot air and still no change. But we can pull start it, and it cranks right up. This doesnt make sense to me. When starting the system voltage is about 12.67 and drops to 10.6 while cranking. Could it be the starter? Do I need to have the computer flashed? I have read several threads and tried several things with no success. The only thing I know to do now is to move to a place with warmer temps!