i have an 05 XLT scab 6.5' bed, and i was wondering what size exhaust pipe i have. currently i have a glasspack on it with dual 45* exits. anyway i was looking to replace the glasspack with a magnaflow universal muffler SIDO but need to know what size inlet and outlet pipes i have.

 

what engine do you have? 5.4L would be 2.5" exhaust, if you still have your stock tip, go out and measure it with your tape measurer