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Possible Restrictions of High Horsepower, High Torque Cummins ISX15 Engines In California For 2024

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  • Possible Restrictions of High Horsepower, High Torque Cummins ISX15 Engines In California For 2024

Most truckers in the industry share a consensus regarding the recent set of laws introduced by the California Air Resources Board – they stink.

Recently, a rumor has emerged suggesting that Cummins will face restrictions in selling its popular X15 big block engines in the state, due to the California Air Resources Board’s decision to limit NOx emissions to 0.02 starting in 2024. Reportedly, Cummins will only be permitted to place a maximum of eight hundred of these engines within California for new trucks for all OEM truck manufacturers. This limitation will affect truck drivers looking for big block, high horsepower, high torque engines which has been Cummins strength.

For the California Trucking industry, this limitation on Cummins availability within the state feels like another addition to a long list of frustrations. These ongoing challenges seem to accumulate like a thousand stinging papercuts.

While the potential ban on Cummins Engines will contribute to the increasing number of negative and hostile remarks about California that are often observed on blogs, Twitter, and YouTube, its impact on effecting change will likely be minimal. Achieving meaningful change will require legal action and political intervention.

For those who continue to operate trucks within the Golden State, it is once again necessary to adapt. In the event that Cummins engines are indeed limited to 800 units for 2024 models, we have compiled a list of alternative engines available, allowing you to make an informed decision.

Who will take the brunt of this change? We believe the heavy haul owner operator consumers, who love the High Horsepower, High Torque Cummins Big Block will end up with limited options. 

Will the lack of the Cummins X15 in your favorite brand test your brand loyalty? Only time will tell. 

Peterbilt and Kenworth Trucks

  • PACCAR MX-13 engine facts:
  • 12.9-liter engine with power and fuel efficiency.
  • Horsepower ratings ranging from 405 to 510.
  • Torque ratings up to 1,850 lb-ft

Helpful links: PACCAR Then and Now, Peterbilt Motor Company 2021 PACCAR MX Engines

Our thoughts on the PACCAR MX-13

“Paccar has put itself in a good position over the last 10 years with lots of support for both parts and service.  The MX-13 is probably the most versatile engine being produced. It has proven itself with an excellent B-Life and history rating. Fairly light weight for the horsepower rating. Very good torque and horsepower range.”

International Trucks

  • International A26 engine facts:
  • 12.4-liter engine with enhanced fuel efficiency.
  • Horsepower ratings ranging from 370 to 515.
  • Torque ratings up to 1,850 lb-ft.

Helpful Links:  International Trucks

Our thoughts on the International A26 engine  

“International has had their issues with engines in the past but with them being bought by VW’s Traton a few years back, we look for them to have a wide range of quality engines and support. They will be competitive in today’s market and in the future.” 

Mack Trucks

  • Mack MP® engine series (MP7, MP8, MP8HE):
  • Horsepower ratings from 325 – 505.
  • Torque ratings up to 1860 lbs.

Helpful Links:  Mack MP Series Engines 

Our thoughts on the Mack MP engine

The Mack MP is a good product and improving, the downside is for the those on the west coast where support is limited. 

Freightliner Trucks / Western Star

  • Detroit™ DD13, DD15 & DD16 engine:
  • A 14.8-liter engine with robust performance.
  • Horsepower ratings from 400 to 600.
  • Torque ratings up to 2,050 lb-ft.

Helpful Links:  Engine Overviews , DD15 Video

Our thoughts on the Detroit DD engine

“A nice engine with excellent support and service with lots of variety for torque and horsepower. However, they have not met the California CARB requirements for 2024 at this time. They may end up in a similar position as Cummins, where they can only sell a limited number of engines in California.”


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