Exhaust pipe size

[nathank]

What is the size of the pipe right at the muffler on my truck? I am looking to replace the muffler but don't want to modify the pipe, just swap it, so what is the in and out sizes on the stock stuff? 99 SCSB Z71 5.3L

[kbone77]

should be 2.5", but an aftermarket muffler is typically shorter in length. so some tubing is usually required.