How to Install Magnaflow MF Series Black Cat-Back Exhaust - Split Rear Exit on your Sierra

Warning: When working on, under, or around any vehicle exercise caution. Please allow the vehicle's exhaust system to cool before removal, as exhaust system temperatures may cause severe burns. If working without a lift, always consult vehicle manual for correct lifting specifications. Always wear safety glasses and ensure a safe work area. Serious injury or death could occur if safety measures are not followed.

Step 1:(Carefully read all instructions before installation) Remove the OEM system by unbolting the inlet pipe assembly at the 2-stud flange. Disengage the welded hangers from the OEM rubber insulators to remove the muffler and tailpipe assemblies from the vehicle. Do not discard or damage the OEM mounting hardware as they will be needed to mount your new MAGNAFLOW performance exhaust system.

Step 2: Begin the installation process by first attaching the supplied threaded hanger to the vehicles driver side rear sub frame (Fig # 1). Secure using the 2 supplied nuts and mount the supplied rubber insulator. Install the inlet pipe assembly by bolting the 2-stud flange to the catalytic converter outlet pipe reusing the OEM hardware. Leave all clamps and fasteners loose for final adjustment. Using the supplied 3.50" clamp attach the muffler to the outlet of the inlet pipe assemply. Locate the welded hangers to the rubber insulators. Next, mount the driver and passenger side mid pipe assemblies using the supplied 3.00" clamps. Secure the extention pipe and the driver and passenger side tailpipe assemblies in the same fashion. Locate all welded hangers to the rubber insulators.

Step 2: With all components mounted loosely, adjust the system for overall aesthetics and clearance of frame & bodywork. (MAGNAFLOW recommends at least 1/2" of clearance between the exhaust system and any body panels to prevent heat-related body damage or fire.)

Step 3: Once a final position has been chosen for the new system, evenly tighten all fasteners from front to rear. The supplied band clamps must be VERY tight to properly align the pipes and prevent leaks (Approximately 40ft-lbs). U-bolt clamps should be tightened to approximately 30-35ft-lbs. Inspect all fasteners after 25-50 miles of operation and retighten if necessary.