2001-2005 Chevy 6.6L Cat Back 4" K4110A Installation

Removal of Original System
1) Start under the vehicle. Find the four bolt flange just behind the catalytic converter, loosen and remove the bolts on this flange.
2) Cut the original system just behind the muffler.
3) Spray the stock hangers with aerosol lube and pry rubber mounts from the system. Leave the rubber mounts attached to the truck for re-use.
4) Remove the old system.
Installation of New Performance System
(Recommended Procedure: Do not fully tighten any clamps until the complete system is installed and aligned.)
1) Hang the muffler in the stock location using the hanger clamp on the outlet. This determines the placement of the rest of the system.
2) Install the first tail pipe into the outlet of the muffler using the hanger clamp already installed. Rotate the pipe as needed to pass next to the shock absorber. This is important, in positioning the tail pipe.
3) Install the second tail pipe on to the outlet of the first tail pipe with a clamp. Rotate as needed to level the outlet behind the rear tire. Attach the hanger clamp in the stock rubber.
4) Install the adapter to the outlet of the front pipe using the four bolts removed earlier. Be sure to install the new gasket.
5) Install the cross member pipe into the adapter placing the bend around, under the cross member. The pipe does not require cutting to fit Crew Cab trucks. For extended cab trucks, approximately 9” needs to be cut off the end with the longest straight section of pipe. (Installation check: measure from the muffler to the four bolt flange to verify the length required).
6) Long beds will need to use a straight pipe extension between the cross member pipe and the muffler. Depending on muffler choice this pipe may very between 15” and 24” in length and will need to be trimmed to length by installer. When using a muffler shorter than 30” the straight pipe extension may need to be used on short beds also.
7) Attach the final piping into the muffler with a clamp.
8) Starting at the front pipe, align and tighten all the pipes and clamps. Start the engine and check for leaks.

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