F150 Cold Weather Battery Drain
 

I am new to this forum .. well any forum actually so I am sorry if this has been a previous question that has been answered a hundred times. We have two Ford F150's on our farm, one is a 2005 5.4l Triton and one is a 2010 4.6l and they both seem to have a similar issue. In the summer we can park both trucks for extended periods and the truck will start no problem. The trouble arises when it becomes well below freezing. In fact it can be below freezing and the trucks will both start no problem but it seems to become a problem when the temperature is well below freezing, the truck batteries seem to develop a drain. A bad drain, the other day it was cold but not that cold and I was able to start the truck no problem, the weather became very cold and within two days cold weather the batteries became dead and the trucks would not start. If the truck sits in the cold for 3-5 days, the battery won't even run the clock. Two days of cold and will attempt to turn over but not enough juice to start the truck and only a few seconds of slow turning over before, click click click.

This problem is a pain and it is hard on the batteries as they eventually are drained and freeze. Both batteries however are newer and posed no problem all summer and most of this winter. Finally an arctic vortex arrived and I fully expected this problem to arise again and sure enough it did. Two trucks with the same problem blows my mind a little. The 2010 was taken to the local mechanic a few years ago and they did talk with a Ford specialist and they replaced some part that nobody seems to have easy access to the record but it seemed to help for awhile, I think (this one is my dads truck). It may have been a relay or something, I just can't recall.

Just wondering if anyone has had this experience? It is directly related to cold. The truck can sit all summer and not drain the battery but as soon as it gets cold enough you need to worry about freezing your fingers -22Celcius or so, sure enough the battery will have drained.

Appreciate any input and thanks for having this forum. I have used this site to help solve many of my issues just reading others similar experiences.