The Pacbrake C40010 is a heavy-duty 4-inch inline-mount PRXB (Pressure Regulated Exhaust Brake) kit engineered for 2003–2007 Ford F-250, F-350, F-450, and F-550 Super Duty trucks equipped with the 6.0L Powerstroke diesel and a 6-speed ZF6 manual transmission. Cast from high-grade ductile iron and treated with Pacbrake’s proprietary Arcor salt-bath nitride surface treatment, this valve housing withstands severe exhaust heat, carbon accumulation, and corrosion. The PRXB design uses a patented spring-controlled pressure-regulating bypass mechanism paired with a 90-degree non-contacting butterfly valve. Unlike standard fixed-orifice brakes that lose stopping power as engine speed drops, the PRXB dynamically maintains peak allowable exhaust backpressure across the engine's operating RPM range, delivering up to 50% more braking power at lower RPM (1,400–1,800 RPM) while protecting exhaust valves and seals from overpressure.

Terrifying brake fade on steep mountain descents, glazed service brake pads, overheated and warped front brake rotors when hauling heavy fifth-wheel or commercial trailers, and rapid friction brake wear are what this inline brake kit eliminates. While manual ZF6 transmission drivers can gear down on descents, the stock 6.0L engine and factory VGT turbocharger provide minimal retarding force, forcing drivers to ride the service brakes constantly under heavy loads. The Pacbrake C40010 creates controlled, reliable exhaust backpressure to slow the engine and driveline mechanically, holding downhill speeds steady and extending foundation service brake pad life by up to 300% to 500%. It is a complete turnkey manual-transmission exhaust brake system, including the inline PRXB valve assembly, vehicle-specific electrical harness with throttle and clutch pedal switches, in-cab switch, and an AMP onboard air system (HP325 12V air compressor, 0.5-gallon air tank, pressure switch, and 25-foot coiled air hose); aftermarket 4-inch OD exhaust adapters (C11342 / C11400) are sold separately for trucks running non-OEM exhaust piping.

It fits 2003–2007 Ford F-250, F-350, F-450, and F-550 Super Duty trucks equipped with the 6.0L Powerstroke diesel, 6-speed ZF6 manual transmission, and factory exhaust tubing (automatic transmission models require kit C40007 with transmission lockup controller; trucks running aftermarket 4-inch OD exhaust require adapter kits).

Fitment

• 2003–2007 Ford F-250 Super Duty 6.0L Powerstroke (ZF6 6-Speed Manual)
• 2003–2007 Ford F-350 Super Duty 6.0L Powerstroke (ZF6 6-Speed Manual)
• 2003–2007 Ford F-450 / F-550 Super Duty 6.0L Powerstroke (ZF6 6-Speed Manual)
• Fits factory exhaust systems (vehicles with aftermarket 4" OD exhaust require two C11342 adapters)
• Engineered specifically for ZF6 6-speed manual transmissions
• Patented PRXB spring-regulated mechanism delivers up to 50% more retarding power at lower RPM (1,400–1,800 RPM)
• Arcor salt-bath nitride coating prevents carbon seizing, galling, and rust
• Includes dedicated clutch and accelerator pedal switches for instant, seamless disengagement
• Complete onboard air system included: HP325 12V air compressor, 0.5-gallon air tank, pressure switch, and coiled air hose
• Turnkey manual-transmission exhaust brake and pneumatic management package

Park the vehicle on a level surface, engage the emergency brake, and disconnect both negative battery cables. Measure and mark a straight 7.25-inch section along the intermediate exhaust pipe downstream of the transmission crossmember along the frame rail, verifying adequate clearance from fuel lines, parking brake cables, and wiring harnesses. Cut out the marked section cleanly using a reciprocating saw or pipe cutter, and thoroughly deburr the inside and outside edges of the remaining exhaust pipe to prevent flow turbulence and exhaust leaks. Slide the exhaust pipe ends into the Pacbrake inline housing flanges, verifying that the exhaust flow direction arrow stamped on the casting points toward the rear tailpipe, and clamp the Marmon flanges securely using the provided heavy-duty V-band clamps. Mount the HP325 air compressor and 0.5-gallon air tank to the vehicle frame rail using the supplied vibration-isolating brackets, routing nylon air lines to the pneumatic cylinder on the brake valve and the 12V air control solenoid. Under the dashboard, install the clutch pedal switch and throttle pedal position switch so the butterfly valve instantly opens when either pedal is touched, preventing engine stalling during shifts or throttle application. Mount the lighted on/off power toggle switch on the dash, connect the fused 12V power supply harness, reconnect the batteries, and road test the truck under closed-throttle coasting to verify immediate, smooth exhaust retarding.