A sure way of testing the alternator is to start the car then remove one of the battery leads (preferbally the positive), then test the pos and neg for 12-17vDC. This will tell you if the alternator is producing electricity. I had to change my alternator and all was ok partly due to the old motorolla only producing 68vDC and the old rusted nuts causing resistance shorting out the charge. If you need to change the alternator, I have a list of part numbers that will get you a straight replacement from your local parts store, OR if you are like me, more power is always the way to go. I will have a new web page up in about 2-3 days @ www.sk1pper.com that has pic of mine and how i put a 140a alternator on. Let me know if you need any more info or if this even helps ... sk1pper landry > > Secondly.... after starting the car and backing it out > for a nice 200 mile drive (now that i can see how much > gas i have), i happened to glance over at my battery > meter.. it was almost to 0.... like the alternator > wasnt working..... it was fine before... i am > wondering if maybe i screwed something up putting the > tankzilla in???? When the needle goes down to the > bottom like that, does it mean the battery, or, worse, > i need to get an alternator???? I am going to > disconnect the tanzilla tommorow and see if that > helps.. if it does maybe its grounding somewhere, if > not... i guess i'll buy the battery and if that doesnt > work, head for the alternator