The aFe Power 49-13003 (Large Bore-HD Series) is a 4-inch mandrel-bent cat-back single-exit exhaust system engineered for 2003–2007 Ford F-250 and F-350 Super Duty trucks equipped with the 6.0L Powerstroke diesel engine. Constructed from 409 stainless steel tubing, this system bolts directly behind the factory catalytic converter to maintain 50-state emissions compliance while significantly increasing exhaust flow. aFe Power designs this kit as a high-value performance alternative to the Mach Force-XP line, incorporating a free-flowing 24-inch straight-through stainless steel performance muffler, welded OE-style bayonet hangers that mount directly into factory rubber chassis mounts, and a bare turn-down style tailpipe exit (without an exhaust tip included).

High exhaust gas temperatures (EGTs) while towing heavy trailers, restrictive factory 3.5-inch exhaust pipe flattening, power-choking internal muffler baffles, suppressed turbo spool response, and rotted factory aluminized tailpipes are what this system eliminates. Factory Ford exhaust systems pinch flow downstream of the catalytic converter, causing exhaust heat to back up into the turbine wheel and cylinders under heavy throttle. The aFe Large Bore-HD system replaces restrictive factory tubing with continuous 4-inch mandrel-bent stainless steel. This lowers peak EGTs, reduces exhaust backpressure, and unleashes the aggressive 6.0L Powerstroke exhaust note without introducing harsh interior cab drone. It is a complete 4-inch cat-back exhaust system including the intermediate extension pipes, performance muffler, over-axle pipe, tailpipe, and OE-style band clamps; exhaust tips, turbo downpipes, and catalytic converter delete pipes are sold separately.

It fits 2003–2007 Ford F-250 and F-350 Super Duty pickup trucks equipped with the 6.0L Powerstroke turbo diesel engine across Regular Cab, SuperCab, and Crew Cab configurations with Short (6'9") or Long (8') beds (does not fit Cab & Chassis models or Ford Excursions).

Fitment

• 2003–2007 Ford F-250 Super Duty 6.0L Powerstroke (All Cabs & Beds)
• 2003–2007 Ford F-350 Super Duty 6.0L Powerstroke (All Cabs & Beds; SRW & DRW)
• Direct bolt-on cat-back installation behind the factory catalytic converter (50-state emissions legal)
• Constructed from 4-inch mandrel-bent 409 stainless steel tubing for corrosion resistance and flow
• Free-flowing 24-inch perforated core performance muffler lowers EGTs and deepens exhaust tone
• Welded OE-style bayonet hangers maintain stable alignment in factory chassis isolators
• Single side-exit configuration behind the passenger rear tire (no tip included; bare 4" tailpipe exit)
• Includes heavy-duty band clamps and installation hardware
• Complete cat-back exhaust kit only

Support the vehicle securely on a heavy-duty lift or tall jack stands and disconnect both negative battery cables. Apply penetrating oil generously to the factory two-bolt exhaust flange nuts behind the catalytic converter and all factory rubber hanger isolators. Remove the two flange nuts behind the catalytic converter using an impact wrench or heat if corroded. Slide the factory exhaust rearward to disengage the metal hangers from the chassis rubber mounts and drop the original cat-back assembly out from under the truck (cutting the over-axle section with a reciprocating saw simplifies removal if working on jack stands). Measure and trim the provided intermediate extension pipe to the exact length specified in the installation guide for your specific cab and bed configuration, then loosely bolt the intermediate pipe to the catalytic converter flange using the factory hardware. Slide the 24-inch straight-through muffler onto the intermediate pipe, supporting it with a jack stand, and install the over-axle pipe and tailpipe sections by slipping the welded bayonet hangers into the factory rubber mounts. Align all pipes to ensure a minimum of 1 inch of clearance around brake lines, shock absorbers, and spare tire heat shielding, then torque all heavy-duty band clamps progressively from the converter flange back to 40–45 ft-lbs.