As a follow-up to my post. I tested my battery and here is what I found
Engine off Battery read 12.67 volts
Engine off with head lights and fans on Battery read 12.35 volts
Bottom line the battery is perfect. Tha Battery is 4 years old I will replace next year. Note always replace the battery in 5 th year, if you wait till the battery goes bad chances are you will burn-out your alternator and for you guys with 3.5 engines it's quite the job to replace. later