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C40109 - Pacbrake PRXB Exhaust Brake Cummins 8.3L ISC 4" Half Marmon

C40109 - Pacbrake PRXB Exhaust Brake Cummins 8.3L ISC 4" Half Marmon
C40109 - Pacbrake PRXB Exhaust Brake Cummins 8.3L ISC 4" Half Marmon
C40109 - Pacbrake PRXB Exhaust Brake Cummins 8.3L ISC 4" Half Marmon
C40109 - Pacbrake PRXB Exhaust Brake Cummins 8.3L ISC 4" Half Marmon
C40109 - Pacbrake PRXB Exhaust Brake Cummins 8.3L ISC 4" Half Marmon
C40109 - Pacbrake PRXB Exhaust Brake Cummins 8.3L ISC 4" Half Marmon
C40109 - Pacbrake PRXB Exhaust Brake Cummins 8.3L ISC 4" Half Marmon
C40109 - Pacbrake PRXB Exhaust Brake Cummins 8.3L ISC 4" Half Marmon
C40109 - Pacbrake PRXB Exhaust Brake Cummins 8.3L ISC 4" Half Marmon
C40109 - Pacbrake PRXB Exhaust Brake Cummins 8.3L ISC 4" Half Marmon
C40109 - Pacbrake PRXB Exhaust Brake Cummins 8.3L ISC 4" Half Marmon
C40109 - Pacbrake PRXB Exhaust Brake Cummins 8.3L ISC 4" Half Marmon
C40109 - Pacbrake PRXB Exhaust Brake Cummins 8.3L ISC 4" Half Marmon
: C40109
In Stock(1)
$995.00
$1,297.27

Part # C40109 PacBrake PRXB Exhaust Brake Cummins 8.3L ISC 4" Half Marmon

Description:

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, 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.

WHAT’S SO SPECIAL ABOUT THE PRXB?
In order to have consistent and effective braking over the entire RPM range, it is important (and necessary) to maintain constant backpressure. To achieve this, Pacbrake’s patented design has incorporated an additional waste gate on the butterfly valve to regulate the amount of exhaust flow that is being passed through. The flow is controlled by a spring-loaded arm, whose pressure rating and location are key factors in the functionality of the PRXB. Located outside of the housing and away from the heat, the spring is able to maintain its strength and durability for years of proper and precise braking performance.




CREATING & MAINTAINING BACKPRESSURE
Backpressure is created by exhaust flow entering the housing, hitting the closed butterfly valve and being forced back out in the direction it came. It is maintained by the pressure-controlled spring that is located on the outside of the exhaust brake housing.

PREMIUM BRAKING PERFORMANCE
As the engine’s RPM increase, the spring compresses and the arm moves away from the butterfly valve, therefore releasing more exhaust flow through the orifice. As the RPMs decrease, the spring releases and the arm applies pressure back onto the plate, covering the hole, and ultimately releasing a smaller amount of exhaust flow.

There is less than a 10% change in backpressure over the entire RPM range on the PRXB




Features & Benefits: 

  • PRXB Delivers Strongest Braking Horsepower
  • Less Wear & Tear On Service Brakes 
  • Ideal For In-City Driving Or Steep, Downhill Grades 

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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

Updated the Vin straight from insurance website. Looking to add an exhaust brake on my 2001 Damon escaper 3979 with a 350 HP idc Cummins. Did not come with one from factory. ( tyler wilson, 08/22/2023 )
Have you visually confirmed there is no exhaust brake? We checked with Spartan and they are telling us your RV came equipped from the factory with a Jacobs exhaust brake.
I have a 2001 Damon Escaper 3979 with a 350 horsepower ISC 8.3 Cummins. Has no exhaust brake from the factory. I want to add one. Do you know what kit or part number I need to order? ( Tyler Wilson, 08/22/2023 )
The VIN you provided is not working for us, can you please check and confirm?
The Pacbrake on my '99 American Tradition with a Cummins 8.3L ISC has failed. The exhaust brake serial number is 022625 and I cannot see a part number. It's 4" pipe.
Which replacement Pacbrake part number along with the clamps part number should I order? Do I need anything else?
Thank you!
Jeff
( Jeff Geier, 07/25/2023 )
If your brake is mounted on a 90 degree elbow, you would want part# C40107 and clamps C10310 & C11350. If it mounts directly to the back of the turbo, you would want part # C40108 and clamps C11355 & C11350.
Last year when leaving Florida after a month stay the exhaust brake stuck closed causing the loss of power/boost. By the time I was able to get off the road a lot of heat built up in the engine area. When the heat dispersed the clapper on the exhaust brake closed. I did not use it the rest of the way home. I was able to lube the brake after returning home and it seems to actuate properly now. It does feel that the brake does not slow the coach as well as it used to. Can you offer ideas as to why it does not slow the coach down like it used to? Did the overheating of the brake/engine area cause something to warp or a gasket to become distorted that I can replace instead of the entire exhaust brake. Any help will be appreciated. Thanks ( Thomas Rouillard, 11/12/2022 )
The heat could have damaged the exhaust manifold gasket which would decrease the performance of the exhaust brake.
Does this PRXB kit include clamps? Or do I have to purchase it separately? Thanks ( Yilun Yu, 09/19/2022 )
The clamps are sold separately.

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