The Paccar PX-9 and Cummins ISL9 (now known as the L9) are essentially the same 8.9-liter, inline-6 diesel engine. The PX-9 is manufactured by Cummins for Paccar, meaning the internal mechanics and core parts are identical, with only brand-specific aesthetic and exterior layout differences.
Key Identical Mechanics (Core DNA)
Displacement: 8.9 liters
Applications: Both are heavily used in medium-duty trucks, fire apparatuses, and vocational vehicles.
Internals: The cylinder heads, camshafts, pistons, and base mechanical blocks are identical.
Key Differences
Branding & Paint: The Cummins ISL9 is typically painted Cummins Red, while the Paccar PX-9 is painted a dark gray/black and features the Paccar name on the valve cover.
Availability: Paccar-branded PX-9s are primarily found in Peterbilt and Kenworth trucks. Cummins ISL9/L9 engines are found in a variety of other makes (like Freightliner and International).
Exterior Plumbing & Layout: Depending on the truck chassis, the layout of accessories like dipsticks, exhaust elbows, and turbocharger mounting angles can vary slightly to fit specific engine bays.
*Monthly payment stated above assumes a secured commercial use loan transaction available for highly qualified commercial loan applicants. Actual loan payment amount and terms may vary. Consumer financing not available for consumers residing in Nevada. Additional state restrictions may apply. Equal opportunity lender. Click here for more state licenses and disclosures. NMLS ID: 1857954. VERMONT RESIDENTS: THIS IS A LOAN SOLICITATION ONLY. CurrencyFinance IS NOT THE LENDER. INFORMATION RECEIVED WILL BE SHARED WITH ONE OR MORE THIRD PARTIES IN CONNECTION WITH YOUR LOAN INQUIRY. THE LENDER MAY NOT BE SUBJECT TO ALL VERMONT LENDING LAWS. THE LENDER MAY BE SUBJECT TO FEDERAL LENDING LAWS. CALIFORNIA RESIDENTS: Financing provided or arranged by Express Tech-Financing, LLC dba Currency pursuant to California Finance Lender License #60DBO54873
Your current browser cannot run our content, please make sure your browser is fully updated or try one of the browsers below.