My goals are for fuel mileage and torque, what's the best choice in a cat back system for my 01 4.2 auto w/3.54 gears? Don't want alot of noise but a little deep rumble would be OK.

Thanks
Al

 

if your looking for milage and torque thats not what your looking for. you might notice an improvement in how the truck responds, but its gonna be a minor one, very minor. if your wanting torque and milage you need to do more than cat back. look into some headers and going true dual with 2 high flow cats and a high performance muffler. thats what you want if you want better milage and performance. if all you can afford is cat back i would suggest saving your money. of course if your simply going for sound cat back is fine. but to really get any performance or milage your gonna have to do more.