I have a 97 T800 Kenworth. The batteries go dead after sitting for about 3 days. We tried checking for a draw but with the 4 batteries we were unsure how to do it. There are also 2 relays by the batteries and we are unsure as to how to test to see if they're working correctly. We replaced the alternator because it was getting hot even without the truck running. The new one does the same thing. We bought the truck used and do not have any technical manuals.