That what I put on my 06 F350 4x4 is a 4" turbo MBRP "cool duals" with 5" stainless tips. Be on the truck for about 5 mouths and love the sound and the performents.
With my 2006 F350 , 373 gears and 20" tires with a 6liter I came get 18.1 mpg towing my tamdem car trailer, at 75mph but with a 9,000lb load it drops to about 15mpg.
I had a 2003 F150 and know a 2006 F350 and every time I put the trucks in any more than 6" of water the horns sounds like a mouse that just got hit by the truck. I moved the horns on my F150 up in front of the rad and it fixed the problem, but the dealer said no warrenty because i moved the...