Look around and see what you like, Then go and have a custom
one made for your truck at an Muffler shop. I had mine made
like a Chevy the Syclone because of the performance. Its a 3"
with a flow master and its stright out the back. Sounds good and
runs great. Also put on Gibson headers.
I have a 3 inch 304 stainless steel exhaust and cat made by ATR on my truck and it sounded good. Once I deleted the muffler, it sounded even better ! Truck gained quite a bit of power after I put it on but, the previous owner had a sub 2 inch exhaust on it. Turbochargers like unrestrictive exhausts...