used PACCAR engines for sale
Used PACCAR Truck Engines
Send us your PACCAR engine serial number and truck VIN, and we search supplier sources nationwide for a used MX-13 or MX-11 that matches your Peterbilt or Kenworth. Availability, condition and freight vary by unit and are confirmed on your quote.
PACCAR models
Used PACCAR engines by model
01MX-13 and MX-11 basics
PACCAR's heavy-duty engines are built for the company's own truck brands. The MX-13 is a roughly 12.9-liter inline six that became available in North American Peterbilt and Kenworth trucks around 2010. The MX-11 is a roughly 10.8-liter engine introduced in North America several years later, aimed at regional, vocational and weight-sensitive applications.
Both engines come from PACCAR's DAF engineering lineage and were adapted for North American emissions rules. They use SCR aftertreatment with DEF, and both have been updated over time for greenhouse-gas regulations.
Because these engines are used almost exclusively in Peterbilt and Kenworth trucks, the truck VIN is one of the best tools for identifying exactly which configuration you need.
02Locating the serial number
The PACCAR engine serial number is stamped on the cylinder block and also appears on the engine identification label. The emissions label lists the engine family and the model year the engine was certified to.
If the labels are hard to read, a Peterbilt or Kenworth dealer can look up the engine serial number and specification from the truck VIN, and the serial number can be read from the engine control module with PACCAR diagnostic software.
Send us photos of the block stamping and the labels when you request a quote. That lets our staff identify the engine generation and calibration family before we search.
- Engine serial number from block or label
- Emissions label model year
- Truck VIN
- Horsepower and torque rating
03Emissions and calibration generations
Early MX-13 engines were certified to the 2010 standards. Later engines were updated for the 2014 and 2017 greenhouse-gas rules, and PACCAR has continued to revise the engines since. Each update can bring changes to the ECM software, sensors, turbocharger and aftertreatment integration.
A later MX-13 is not automatically a better fit for an earlier truck. The truck's chassis electronics, dash and aftertreatment are matched to the engine generation it was built with. We match on emissions year and calibration family to avoid wiring and software conflicts.
If your truck has the PACCAR automated transmission, the engine and transmission controllers must communicate correctly, so let us know the transmission model when you ask for a quote.
04Horsepower and torque
The MX-13 has been offered in ratings from roughly the low 400s to around 500 horsepower, with torque ratings matched to linehaul and vocational duty. The MX-11 is rated lower, generally in the mid-300s to around 430 horsepower range.
Ratings are set in the engine software and can depend on the truck model and drivetrain spec. If you want a different rating from your original, tell us so we can check it against your transmission and the engine generation.
05Peterbilt and Kenworth considerations
Even within the PACCAR family, Peterbilt and Kenworth installations are not identical. Engine-mounted parts, cooling package connections, air intake routing and harness interfaces can differ between a Peterbilt 579 and a Kenworth T680, and between those trucks and conventional models like the Peterbilt 389 or Kenworth W900.
PACCAR also sold the PX-7 and PX-9, which are Cummins-based medium-duty engines rather than MX-series engines. If your Peterbilt or Kenworth medium-duty truck has a PX engine, the identification and matching process follows the Cummins approach with an ESN and CPL, so tell us which engine you have.
Commercial-Engines.com is independent and is not affiliated with PACCAR, Peterbilt, Kenworth or DAF. Brand and model names are used only to identify engines.
06What to tell us when you call
Have your engine serial number, truck VIN and emissions year ready. Let us know whether you need a complete engine or a long block, and which components you plan to reuse, such as the turbo, aftertreatment and accessories.
Describe the failure if you know it. That helps us understand what parts of your current engine may be reusable and what to look for in a replacement. We search supplier sources nationwide and confirm the details of any available unit on your quote.
Applications
Trucks commonly running PACCAR engines
Factory engine options changed by model year. Always confirm against your engine serial number and VIN.
- The MX-13 is common in Peterbilt 579 and 567 and Kenworth T680 and T880 trucks, but installation parts and harnesses differ between brands and model years, so match by serial number and VIN.
- Some Peterbilt 389 and Kenworth W900 trucks were spec'd with the MX-13; confirm the engine generation and cooling package before sourcing.
- The MX-11 appears in regional and vocational Peterbilt and Kenworth configurations and is not interchangeable with the MX-13 without significant changes.
- Medium-duty Peterbilt and Kenworth models with PX-7 or PX-9 engines use Cummins-based designs and should be matched by Cummins ESN and CPL rather than as MX engines.
FAQ
PACCAR engine questions
Who builds the PACCAR MX-13?
The MX-13 is built by PACCAR for its own truck brands and is based on engineering from DAF, PACCAR's European truck division. In North America it is used mainly in Peterbilt and Kenworth trucks.
Can I swap an MX-11 into a truck that had an MX-13?
Not as a simple swap. They are different engines with different ratings, mounting and calibration. Replacing an MX-13 with an MX-13 of the same generation is the straightforward path.
Where do I find my PACCAR engine serial number?
It is stamped on the block and shown on the engine identification label. A Peterbilt or Kenworth dealer can also look it up from the truck VIN.
Are the PX-7 and PX-9 PACCAR engines?
They are PACCAR-branded medium-duty engines based on Cummins designs, so they are identified differently from MX engines. Tell us the engine label details and we will search accordingly.
Does a 2017 MX-13 fit a 2012 truck?
Not reliably. Later engines have different software and sometimes different hardware and aftertreatment integration. A replacement should match the emissions year and calibration family of your original engine.
Are you affiliated with Peterbilt or Kenworth?
No. Commercial-Engines.com is an independent sourcing company. We search supplier sources nationwide for used engines that match your configuration.
Ready when you are
Need a PACCAR engine? Send the serial and we'll start the search.
Have your engine serial number, CPL and VIN handy. If you don't, we'll help you find them.
Commercial-Engines.com is an independent supplier of used commercial truck engines and transmissions. Manufacturer names, model names and part numbers are used for identification only and do not imply affiliation with, or endorsement by, any manufacturer. Read the full disclaimer.