Electrical Problem

Tonight when I was getting into my XJ to drive to work I saw that the volt gauge was reading at the 9V mark or the bottom of the gauge, I didnt think much of it but about 15 min into my drive the lights on the dash started to dim and my headlights started to dim, then about 2 min later the radio power started to kick on and off, well I pulled over and called a friend and we went and got a new battery, got it in and well the volt gauge only read at about 12V, then about 2 min into the drive home it droped back down to the bottom of the gauge. So my question is do you think its the alternator? thats about the only thing I can think of. I am going to call the stealership in the morning to schedule some work under the extended warranty.

Yup, sounds like the alternator is taking a crap! Should see if they will cover the battery that you had to purchase, becuase when the alterntor dies, it usually take the battery with it anyway!