Help! I have a 1999 F250 that is having problems starting in cool to cold weather. New batteries, not the problem. Ford house checked glow system and all is ok (according to them). I have to crank several times to start if she starts. I do cycle glow plugs several times before trying to crank over. Finally I plug in the block heater and all is well after a short wait. My theory is that when the oil is cold and thick the old starter just does not having enough hump in it to do the job. Starter roars to duty and duys off rapidly. When plugged in for a while starts right up. What else could plugging the block heater in do to help the starting other than reduce the torque resistance by thinning the oil?