4" x 9" x 18" Oval Superflow Stainless Muffler (2.5" In Offset 2.5" Out Offset) by Gibson Performance
Gibson High Performance Superflow Mufflers deliver the powerful "big block" sound at the tailpipe with more usable pulling power and torque! Gibsonís superior design reduces cab noise (drone) without sacrificing power or sound quality . By baffling and chambering their mufflers, (vs cheaper packed or screened mufflers - nothing to blow out) Gibson mufflers promote better volume efficiency with unrestricted flow. Even better, the added thickness of the muffler case and heavy duty tubing, along with a superior stainless steel design, all contribute to a long and productive life for your new performance muffler.
The part number for this item is 55172s . The inlet and outlet diameters are below:
4" x 9" x 18" Oval Superflow Stainless Steel Performance Muffler (2.50" Inlet Offset) (2.50" Outlet Offset) by Gibson Exhaust