Assuming that this car has the 6.0 LS2 V8, it's a pretty stout engine IF it's well maintained. I'd ask if the dealer has any service records or check the glove box for receipts. If you know the previous owner or the dealer knows the previous owner, call him/her up and ask how often the car was serviced and what's been done to it etc.
If it's got a lot of performance modifications on it, i.e. intake, exhaust system, short throw shifter (if equipped with manual transmission), custom tune etc., then most likely those 117,000 miles were really hard miles and the car had the hell run out of it at times. Which obviously takes a toll on the engine, even with supporting modifications.
Here's my overall recommendation: Drive the car again, on the highway and in town. See how it feels with the braking, acceleration. Make sure the alignment is okay and that the car doesn't veer to the side when you let go of the steering wheel. Roll the windows down and listen for any whining and squealing noises, especially when turning the wheel. Check all electrical functions in the car.
Remember, the car was traded in for a reason. If it's at a cheap price, there's a reason. And with any high mileage car, things are bound to start breaking. It's inevitable. But if you have the budget to buy the car and replace things when the time comes and the car suits your needs, go for it. Otherwise, save your money and look elsewhere. Don't pounce on the first car you see until you do your research, no matter how appealing the deal may be.