Welcome to the board. How do you like that 5.3L? I'm thinking of swapping one into one or both of my old trucks.
I put this one through a couple of good hard workouts, and it's done very well. It's got plenty of torque for a small block. With the cold air intake it's about 325 Lb/Ft of torque, and about the same in HP.
On long trips with 2 people and our luggage, plus my normal array of tools on board, it'll pull 21-22 mpg, too. According to the trucks computer, the life time average mpg's is 17.8. Consider that I keep about 300 lbs of tools in the tool box, at all times, and then there's my 205 lbs.
Its a great little workhouse that's easy to manage and with a lot of pep. The 5.3 now has 61K miles on it, and it's been very reliable.
The 4.8L is a little worker too, though. It gives up about 15 HP and about the same in Tq to the 5.3L, but that can easily be made up with some simple bolt on. It'll make about 22 mpg, too. Mine has 223K miles on it, and has never had a single repair to the engine (or drive train). The only engine related part that was replaced is the A/C compressor, and I replaced that at about 220K miles. Other than that, just regular PM's and Mobile one.
If you've got a Chevy or a GMC pick up that due for an engine replacement, I'd highly recommend either, based solely on my experience with them.
