like I said give me the readings and that will help me to figure out whats going on. what is cold in your area? battery voltage will drop with temperature by about .01 volts for every 10 degrees Fahrenheit, starting around 80 degrees (which is the rated operating temperature) and going down to about 40 degrees, this is not much. At 80 degrees a fully charged battery should produce 12.68V, at 30 degrees a fully charged battery should read 12.58 and at 0 degrees it should read 12.51.

just put the meter probes on there corresponding battery terminals to get the readings, then start the truck and read them again at idle.

to measure the current draw, simply disconnect either one of the cables from the battery and put your DMM inline form the terminal to the cable and set the DMM to read milliamps (mA). If the meter is not auto-ranging, select the 100 or 1000 mA scale,

 

I appreciate the help, I won't really get out to troubleshoot until Friday and I will post the current and voltage. I only really ran into problems with low voltage when we had 3 days down in the teens (F).

Unfortunately I got rid of my Fluke Multimeter from engineering school and had to buy a Walmart special (non auto-ranging but digital). It works though.