2007 Silverado Exhaust Ticking/Popping after ignition is off!

I just bought a NBS 2007 Silverado with 15k miles on it.  After my first night of driving it home I pulled into the garage and shut it off.  Keep in mind, I find some exhuast ticking/popping common.  However, this was the loudest most frequently occuring ticking sounds I have ever heard.  It could be heard in our house it was so loud.  Has anyone else noticed that it, does it seem louder than usual to anyone else?  I wonder what the cause is, and should it be a concern?  Thanks.

I can say mine was pretty load too but i only had the factory exaust on it for 280 miles
and i put duels on it now
but i noticed it when i stopped for gas on my first trip because i bought it and next morning i took it on a 300 mile trip.
got gas half way there and i heard it then.
and then again when i got to exaust shop where i got new pipes on.
 

I have about 8K on mine and it has always ticked and popped as well.  It is definately louder than any other vechicle I have ever owned.

its your heat sheild under the vehcle. cooling off this is a normal issue. and their really isnt anything they can do about that.

i got to say i dont have it at all anymore
mine must been more of the fact. muffler

After the inside of the cats smut up and the heat shield gets used to the temp changes, it'll quiet down. My ma's Envoy did the same thing when it was new and we though it was a little out of the ordinary to be making popping noises that loud, but after it hit about 30k I didn't notice it anymore.

Strange, I have have an 07 tahoe, my second one and the popping is minimal.  On this silverado now with 15k miles I shut it off in my garage and got out of the vehicle and ran for cover.  I have never heard anything like this.  I will wait and see if it continues and see if it is as loud next time.  Thanks for the replies guys, i will keep you informed.

I guess its louder than I am envisioning. lol Running for cover!

Yeah, that really wasnt a joke.  I have had a lot of vehicles and have never heard anything like it.  As I mentioned, I have had a couple 07 Tahoes that have the same engine and basically the same exhaust.  This Silveado had me scared and I truly thought it was going to blow!