After being in my garage for 3 different 10 day periods. my battery was completely drained.. so far, I've already gone through 2 batteries and am currently on my third one, since purchasing my 05GT. on 2/13/05 took the car back to my dealer, and all they did was replace the battery, their service dept. could not determine nor diagnose the cause, or should I say, thats what they claimed.. so after taking the car back the second time, the dealer recommended that either I use a trickle charger, or have them install a battery disconnect switch, if the car is not to be used for more than a week which I feel is absolutely ridiculous...especially for being a 25k+ new car. if anybody has any suggestions, ideas, recommendations who has also experienced similar problems..I'd be extremely greatful for any advice and input...would it also be possible that the shaker 500 may be the cause of my batteries to drain ??? I've heard that some shaker 500's that were installed prior to April were defective and that Ford was well aware of this issue and has since taken steps to correct any bugs that were causing battery discharge problems...if anyone has any info. about this.. please let me know...thanks much, torch red 05 mustang GT