Flo Pro 2017-2019 Duramax 4″ Downpipe Back Single 3500 6.6L, Cab & Chassis, w/ OEM 4-BOLT Flange With Muffler, Crew Cab ONLY! – FLO 887
In 2017, GMC made a production change in the connection between the catalytic converter and the turbo direct pipe on the L5P. Please ensure you have the newest 4-bolt style flange before ordering any of the kits
* IMPORTANT NOTE: These kits will only fit models equipped with center mounted rear fuel tank on CREW CAB Cab & Chassis model 3500’s.