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PacBrake C40106B PRXB Exhaust Brake for Caterpillar 3126B, 3126E & C7 – 4" Full Marmon Turbo Flange

PacBrake C40106B PRXB Exhaust Brake for Caterpillar 3126B, 3126E & C7 – 4" Full Marmon Turbo Flange
PacBrake C40106B PRXB Exhaust Brake for Caterpillar 3126B, 3126E & C7 – 4" Full Marmon Turbo Flange
PacBrake C40106B PRXB Exhaust Brake for Caterpillar 3126B, 3126E & C7 – 4" Full Marmon Turbo Flange
PacBrake C40106B PRXB Exhaust Brake for Caterpillar 3126B, 3126E & C7 – 4" Full Marmon Turbo Flange
PacBrake C40106B PRXB Exhaust Brake for Caterpillar 3126B, 3126E & C7 – 4" Full Marmon Turbo Flange
PacBrake C40106B PRXB Exhaust Brake for Caterpillar 3126B, 3126E & C7 – 4" Full Marmon Turbo Flange
PacBrake C40106B PRXB Exhaust Brake for Caterpillar 3126B, 3126E & C7 – 4" Full Marmon Turbo Flange
PacBrake C40106B PRXB Exhaust Brake for Caterpillar 3126B, 3126E & C7 – 4" Full Marmon Turbo Flange
PacBrake C40106B PRXB Exhaust Brake for Caterpillar 3126B, 3126E & C7 – 4" Full Marmon Turbo Flange
PacBrake C40106B PRXB Exhaust Brake for Caterpillar 3126B, 3126E & C7 – 4" Full Marmon Turbo Flange
PacBrake C40106B PRXB Exhaust Brake for Caterpillar 3126B, 3126E & C7 – 4" Full Marmon Turbo Flange
: C40106B
In Stock(10)
$995.00
$1,297.27

PacBrake Special


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Sale ends 03/31/2026 at 11:59:59
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PacBrake C40106B PRXB Pressure Regulated Exhaust Brake for CAT 3126B, 3126E and C7 Truck and Bus Applications


PacBrake’s flagship product, the PRXB (pressure regulated exhaust brake), is the unquestioned leader in the supplemental brake industry. The patented PRXB design delivers the strongest braking horsepower, greatest speed reductions and shortest stopping distances possible without the use of service brakes. It maintains optimum retarding performance by maximizing the exhaust backpressure throughout the entire RPM range. Unlike a typical exhaust brake, which requires high RPMs to work properly, the PRXB delivers constant exhaust pressure (braking) as early as 1200 RPM through to the maximum allowable RPM. 

Controlled by a master ON/OFF switch, you can choose when to engage the exhaust brake with just the lift of your foot from the throttle pedal. PacBrake’s exhaust brakes provide whisper quiet supplemental braking that allows service brakes to be used much less, ultimately saving you money. They have the ability to be left on all the time, making it ideal for in-city driving or for steep, downhill grades. This product pays for itself as less wear on the brake pads means fewer brake jobs.

Product Benefits:

  • Provides 50 percent More Braking Power at Lower RPM's. PRXB gives you the best hold-back in the 1400-1800 RPM range (where you typically drive).
  • The spring controlled pressure regulated mechanism on the exhaust brakes protects against engine over-pressure.
  • When the brake is deactivated, exhaust flow is unrestricted and won't interfere with power output.
  • Patented 90 degree Non-contacting Butterfly Valve is specially engineered to maximize back-pressure while preventing seizing.
  • The brakes use industry exclusive Arcor nitride coating on housing and components which increases resistance to wear and corrosion while strengthening the exhaust brake and adding lubricity.

Applications:

  • Ford F650 / F750 with Cat 3126B / 3126E / C7
  • Freightliner FL50 / FL60 / FL70 / FL80 with Cat 3126B / C7
  • Freightliner M2-106 with Cat C7
  • Chevrolet/GMC C6500 / C7500 / C8500 with Cat 3126B / 3126E / C7
  • Chevrolet/GMC T6500 / T7500 / T8500 with Cat 3126B / 3126E / C7
  • Kenworth T300 with Cat 3126B / 3126E / C7
  • Peterbilt 320 with Cat 3126B / 3126E / C7
  • Peterbilt 330 / 335 with Cat 3126B / 3126E / C7
  • Sterling 8000 with Cat 3126B / 3126E / C7
  • Sterling HX Series with Cat C7
  • Thomas Bus Saf-T-Liner with Cat C7
  • Western Star with Cat 3126B / 3126E / C7
  • Motorhomes with Cat 3126B / C7 with 4" Full Marmon Turbo Flange

Other Information:

  • Delivers the strongest braking horsepower, greatest speed reductions, and 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
  • Withstands extremely high exhaust temperatures
  • Compliant with latest emission regulations
  • Severe duty and military approved
  • No risk of engine overpressure



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WARNING: Products may contain one or more chemicals known in the State of California to cause cancer and/or birth defects or other reproductive harm. For more information, visit www.P65Warnings.ca.gov

Are there gaskets required between the pacbrake and turbo and exhaust side, and if so what are the part numbers needed on the C40106B exhaust brake,
Thank You
( Bill Brainard, 03/03/2025 )
No, there are no gasket used, just the v-band clamps.
Does this item require a core return?
C40106B
( Bill Brainard, 02/26/2025 )
No, it does not. 
I have a 2005 Freightliner M6 chassis with a C7 Cat motor. I would like to add an exhuast brake. What parts do I need to complete the installation? ( ROBERT MATHERLY, 05/02/2024 )
You would need the brake part # C40106B, mounting group part # C11546 and control group part # C20123. PacBrake recommends using the factory Freightliner exhaust brake switch part # A06-37217-056 as well. 
I have a 2007 bluebird vision school bus with a CAT C7 wex series (built in 2006). What parts would I need to install the exhaust brake? Also, does it require any welding or can it all be done with clamps?

Thanks.
Mark.
( Mark Anderson, 12/16/2023 )
We do not have a vehicle specific listing for this but it can be done, we just need additional information. What would be really helpful, are some pictures of the turbo and the exhaust coming off of it. This will determine if the brake can be mounted to the backside of the turbo or if we would need to do an inline brake further back in the exhaust system. We also will need to know if you have on-board air to operate the brake. Last bit of info, we would want to verify you have a 4th generation Allison, if you could get the Allison serial # off the data plate on the side of the transmission we will be able to determine.
99 kw t300
Cat 3126
10spd gear box
What would i need to make this work?
( Chris, 05/03/2023 )

If it's a 3126 then you would want part # C40105, if it's a 3126B then you would want C40106B. Either brake will take mounting group part # C11558 and control group part # C10319.

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