2005 monte carlo 3.8L battery draining and already replaced battery and alternator.. what else could be the problem?

SOURCE: when do i change the transmission fluid 2005 monte carlo?

Well, I'm not really sure what the manufacturer's recommended interval is... But to be honest with you, once every 100000 kms, or 5-6 years is plenty for a transmission fluid/filter change is enough (yes, there is a filter inside the pan of the transmission, assuming it's an automatic). But, if you notice problems earlier (transmission starting to slip, fluid discoloration, or any other transmission related driveability issues) the first thing to do would be to do a transmission oil/filter change as soon as you can. Beware of these places that offer a transmission flush, that's about as useful as putting winter air in your tires, and costs money for nothing.

SOURCE: monte carlo 2001 ss 3.8 V6

is the battery good if it is shorted out it will do this or if the charging system is not working

SOURCE: need to replace alternator on 1998 chevrolet monte carlo

Nope, it has two bolts one towards the front and one at the back underneath. Be careful of the one in the back as the nut is tricky to get on. You don't need to remove the bracket.

SOURCE: battery being drained and alternator already been replaced

have you checked your drive belt and the tension pully ? it sounds like the belt is'nt turning the alternator fast enough to supply the battery

SOURCE: 2001 Monte Carlo battery goes dead over night

9 times out of 10 it is the factory amplifier. I had this same problem and it was the amplifier. Disconnect the amp located in the trunk by the speakers and see if the drain continues. You will not have music, but having the amp replaced with an aftermarket one will solve this problem,