As some of you many know i recently bought my first diesel truck and of course i went all in and got the big ole' f-350 sd drw. Well here's my problem. i have to charge the batteries each and every day to get the started. yes its cold but i have the heater plugged in. the only extra option on this truck is the lift gate it has an electric motor. would this be the cause of sucking the juice from my batteries? or is my alternator just not charging either of them?
i can supply pics and a video if im able to put one on this site. please help!!

 

Here is an example of how to find a Parasitic Draw.

 

Something else that will let you know how your electrical system is doing on a daily basis is one of these

 

With the truck off, it the alt warm? Try and unplug the alt on a weekend and see if the batteries went dead.

 

the alt is cold but i but has to do with the temp being 20 degrees outside and the wind cutting through me like a knife.

 

this was helpful to gain knowledge from. only problem i am having is i don't own a multi-meter.... i will be purchasing one though

 

Another great link! Thank you!