Just thought I'd put in my .02 for those thinking about exhaust. I decided to save myself a ton of cash and paid the local muffler shop to cut out my muffler and weld in a straight 3.5 inch pipe.....and I couldn't be happier. Great sound (without being so loud in the cab), great throttle response, and I do notice a bit of a power increase. And by saving the 500 or so bucks, I can afford to get a tuner. : )
'02 LB7