The aFe Power 49-43009 (Mach Force-XP Series) is a premium 4-inch mandrel-bent cat-back single-exit exhaust system engineered specifically for 2003–2005 Ford Excursions equipped with the 6.0L Powerstroke diesel engine. Fabricated from 100% durable 409 stainless steel tubing, this direct-fit system bolts directly behind the factory catalytic converter to keep the vehicle 50-state emissions legal while maximizing exhaust gas velocity. aFe Power constructs this kit with an Excursion-specific over-axle routing designed to cleanly clear the rear-mounted 44-gallon fuel tank and rear suspension components, a high-flow straight-through 24-inch perforated stainless steel performance muffler, welded OE-style bayonet hangers, and a massive 5-inch angle-cut, dual-walled polished 304 stainless steel exhaust tip featuring a laser-etched aFe Power logo.

Excessive exhaust gas temperatures (EGTs) when towing heavy travel trailers, restrictive factory 3.5-inch tubing, power-robbing OEM chambered muffler baffles, muffled turbo spool sound, and rust-through damage on factory exhaust components are what this system solves. The factory Ford Excursion exhaust system restricts airflow behind the catalytic converter with crimped radius bends and a dense internal baffle muffler, trapping intense thermal energy inside the tailpipe section. The aFe Mach Force-XP system significantly increases exhaust flow, lowering peak EGTs, reducing exhaust backpressure against the variable geometry turbo (VGT), improving low-end throttle response, and unleashing an aggressive diesel tone without creating interior drone in the large Excursion cabin. It is a complete 4-inch cat-back exhaust system including the intermediate pipe, performance muffler, over-axle pipe, tailpipe, 5-inch polished tip, and heavy-duty OE-style band clamps; turbo downpipes and catalytic converter test pipes are sold separately.

It fits 2003–2005 Ford Excursion 4WD and 2WD models equipped with the 6.0L Powerstroke turbo diesel engine (engineered exclusively to clear the rear chassis layout and aft-axle fuel tank unique to the Excursion SUV platform; does not fit Super Duty pickup trucks).

Fitment

• 2003–2005 Ford Excursion 6.0L Powerstroke Turbo Diesel (4WD & 2WD)
• Engineered exclusively for the Ford Excursion SUV platform and aft-axle fuel tank configuration
• Direct bolt-on cat-back installation behind the factory catalytic converter (50-state emissions legal)
• Fabricated from durable 409 stainless steel for superior corrosion resistance and longevity
• Smooth 4-inch mandrel-bent tubing maximizes exhaust flow and gas velocity
• High-flow straight-through 24" perforated stainless steel muffler lowers EGTs without in-cabin drone
• Includes premium 5-inch inlet/outlet angle-cut, dual-walled polished 304 stainless steel exhaust tip
• OE-style bayonet hangers maintain position and slide into factory rubber isolators without welding
• Includes heavy-duty 4" band clamps and installation hardware
• Complete cat-back exhaust system kit

Support the Excursion safely on a vehicle lift or tall jack stands placed under the frame, ensuring the rear axle hangs free, and disconnect both negative battery cables. Spray penetrating lubricant onto the factory exhaust flange bolts behind the catalytic converter and all factory rubber hanger isolators along the frame rail. Remove the factory two-bolt flange nuts behind the catalytic converter using an impact wrench or heat if corroded. Slide the stock exhaust system rearward to slip the hangers out of the chassis rubber isolators and lower the entire OEM cat-back assembly to the floor (cutting the stock over-axle pipe with a reciprocating saw just behind the muffler will significantly simplify removal around the rear axle and aft-axle fuel tank). Install the aFe intermediate pipe onto the catalytic converter outlet flange using the provided hardware, leaving it finger-tight for final adjustments. Slide the straight-through 24-inch muffler onto the intermediate pipe, supporting it with a stand, and guide the over-axle and tailpipe sections over the rear axle housing and around the aft fuel tank heat shield, sliding the welded bayonet hangers directly into the OEM rubber mounts. Install the 5-inch polished stainless steel tip onto the tailpipe exit behind the rear passenger tire, adjust the entire assembly to ensure a minimum of 1 inch of clearance around the fuel tank, rear sway bar, shock absorbers, and spare tire, and torque all heavy-duty band clamps progressively from front to back to 40–45 ft-lbs.