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PRXB exhaust brakes deliver constant backpressure throughout the entire operating RPM range for unmatched stopping power

PRXB exhaust brakes offer the highest braking power to lowest price ratio available. Pacbrake's flagship product is the unquestioned leader in the supplemental brake industry. It has changed the way people think about exhaust brakes by providing performance, safety and durability that is unmatched by any other exhaust brake on the market.

Upgrade any standard exhaust brake to a PRXB for an improved design and a longer lasting brake with significantly increased performance

Tow & haul with complete control!


PRXB Highlights

  • For the majority of diesel engines
  • Delivers the strongest braking horsepower, greatest speed reductions & shortest stopping distances possible without the use of service brakes
  • Maintains optimum retarding performance by maximizing the exhaust backpressure throughout the entire operating RPM range
  • Delivers maximum exhaust pressure (braking) as low as 1200 RPM through to the maximum allowable engine RPM
  • Provides increased performance and peace of mind with technology that protects the engine from the potential of overpressure


PRXB Features & Benefits

  • Delivers maximum backpressure throughout the entire operating RPM range
  • Withstands extremely high exhaust temperatures
  • Compliant with latest emission regulations
  • Severe duty & military approved
  • No risk of engine overpressure
  • Decreased service brake wear

PRXB Specifics

  1. STAINLESS STEEL SEALED AIR CYLINDER Hard anodized aluminum & stainless steel body & shaft with high performance seals
  2. AUTOMATIC LOW RPM ADJUSTMENT Optimum retarding performance maintained by maximizing exhaust backpressure throughout the entire operating RPM range
  3. MAXIMUM ALLOWABLE EXHAUST BACKPRESSURE LIMIT Designed & factory preset to meet standards & requirements set by the engine manufacturer
  4. NO OVERPRESSURE POTENTIAL Spring controlled, pressure regulated mechanisms
  5. 90° CLOSING, NON-CONTACTING BUTTERFLY VALVE Designed to maximize backpressure while preventing seizing
  6. ARCOR® NITRIDE HOUSING & COMPONENTS Industry exclusive process that increases resistance to wear & corrosion while strengthening & adding lubricity
  7. FREE FLOW EXHAUST When deactivated, exhaust flow is unrestricted and won’t interfere with power output
  8. PRECISION MOUNTING SURFACE Both contacting surfaces are machined, eliminating the need for troublesome gaskets

PRXB Exhaust Brake Operation

  2. ARM (Operated By Spring)
  4. ORIFICE (Hole In Butterfly Valve)
  5. WASTEGATE (Covering Orifice)
  7. BACKPRESSURE Maximum Over The Entire Operating RPM Range

Every PRXB Automotive Kit comes with everything required for a complete installation. PRXB Kits Include:

  • PRXB Exhaust Brake
  • Controller (when required for application)
  • AMP Onboard Air Kit, which includes: HP325 Series Compressor, ½ Gal Air Tank, 25ft Coiled Air Hose, Air Accessories & Fittings


Explain an InLineMount Exhaust Brake?

InLineMount – Some vehicle configurations do not allow for clearance around the turbocharger, for installation of a DirectMount exhaust brake, these applications require an InLineMount. Inline exhaust brakes require a minimum 7" of straight exhaust pipe which is then cut out and exhaust flange adapters are installed in its place. Ensure the exhaust brake is mounted as close to the turbocharger as possible and away from road spray.

NOTE: Clamped joints that exist between the brake and the engine must be welded to ensure that the joints cannot separate or leak under pressure. No flex pipe is allowed between the exhaust brake and the turbocharger.

Explain an DirectMount Exhaust Brake?

DirectMount –This application is preferred because of the reduced number of connections between the exhaust brake and the turbocharger. The mating surfaces are both machined cast iron which eliminates any chance of exhaust leaks.

For vehicles with straight back systems shortening of the header pipe is required to maintain an adequate amount of flex pipe. Vehicles with a 90° header pipe use a cast elbow to interface with the stock header pipe. Pacbrake offers replacement header pipes for some truck models.

When should a turbo mount with a cast adapter be used?

This application is the preferred option for vehicles with a tight 90° bent header pipe post turbocharger. The cast adapter is constructed from cast iron with machined mating surfaces on both ends, eliminating any chance of exhaust leaks.

Warranty Registration

Register your product for warranty HERE.