---
title: PACCAR MX-13 Big Block Engine | Performance Partners | Pierce Mfg.
description: The PACCAR MX-13 engine is an exclusive offering on Pierce custom chassis. The rigorously tested 12.9 liter engine offers peak torque at 1,000 RPM.
---

# PACCAR MX-13 Big Block Engine

![PACCAR MX-13 Big Block Engine Locations as of March 2026](https://www.piercemfg.com/hubfs/PACCAR-Map_4250x2860_02.png)

## The New Heart of Heavy-Duty Performance

#### Pierce + PACCAR MX-13

**[PACCAR MX-13 BROCHURE](https://www.piercemfg.com/pierce/literature/paccar-mx-13-brochure?hsLang=en-us)**

![imgi_4_PACCAR_ROLLING](https://www.piercemfg.com/hubfs/imgi_4_PACCAR_ROLLING.jpg)

## Partnership

![PACCAR_Engine](https://www.piercemfg.com/hs-fs/hubfs/Press_Releases/SanJose2021/PACCAR_Engine.jpg?width=800&height=534&name=PACCAR_Engine.jpg)

 

Since 1913, Pierce has been the leading global fire truck manufacturer producing highly customized, carefully designed and engineered pumpers, tankers, aerials and rescue units. 

For more than 60 years, [PACCAR](https://paccarpowertrain.com/#section-integrated-powertrain) has engineered and produced innovative, reliable, productive and efficient heavy-duty diesel engines for customers throughout the world. PACCAR operates two technologically advanced engine research and development centers with 47 engine test cells and a powertrain dynamometer to enhance engine design and manufacturing capabilities.

We are bringing together two premium brands, providing a first-class engine for custom fire apparatus. 

> *Although the PACCAR engine was going to be a change from the normal for us, we knew the long history of  PACCAR and the affiliation with Kenworth and Peterbilt and having that knowledge, along with having several distributors/shops here in Florence, we knew PACCAR was going to be the right choice for our investment. Since receiving the apparatus, we have been very pleased with its performance and have had no issues with the engine itself or with the DEF system associated with it.*
> 
> ***Shannon Tanner  
> ******Fire Chief | City of Florence Fire Department  
> [View the Florence Fire Department Aerial](https://www.piercemfg.com/customers/new-deliveries/florence-fire-department-aerial-35809?hsLang=en-us)***

## MX-13 Overview

The PACCAR MX-13 engine is built by PACCAR at their Columbus, Mississippi facility. From the CNC machining centers for engine blocks and cylinder heads to robotic assembly, MX-13 engines are manufactured to extraordinarily high standards. In order to achieve excellent  repeatability and high quality, the plant utilizes torque controlled tooling, and all engines are 100% hot tested before they leave the facility.

The PACCAR engine plant in Mississippi opened in 2010 to build PACCAR MX-13 engines exclusively for Kenworth and Peterbilt trucks which are also owned by parent company, PACCAR. In 2021, PACCAR began offering the MX-13 engine to Pierce exclusively for the fire truck industry.  

The PACCAR MX-13 engine incorporates industry-leading design features that improve uptime, optimize fuel economy, reduce maintenance costs and maximize your return on investment. 

**Optimized Weight + Fuel Economy**

- Compacted graphite iron castings 
    - 75% stronger + 20% lighter than grey iron
- High pressure common rail fuel injection 
    - Improved combustion efficiency

**Outstanding Low-End Torque**

- Peak torque at 1,000 rpm

**Incredibly Durable**

- Weatherproofed wiring - no cable rub
- Fractured cap technology - high shear strength

**Ultra Quiet + Ultra Smooth**

- Rear engine gear train design reduces noise
- Maximum engine braking power over a wide range of speeds reducing the need for multiple gear shifts

 

 

![PACCAR Engines - MX-13 - HiRes](https://www.piercemfg.com/hs-fs/hubfs/PACCAR%20MX-13/PACCAR%20Engines%20-%20MX-13%20-%20HiRes.png?width=1555&height=201&name=PACCAR%20Engines%20-%20MX-13%20-%20HiRes.png)

 

![paccar-mx-13-fire-truck-engine](https://www.piercemfg.com/hs-fs/hubfs/Blog/Blog%20-%206%20Summer%20Tips%20to%20Keep%20Your%20Fire%20Truck%20Cool/paccar-mx-13-fire-truck-engine.jpg?width=800&height=534&name=paccar-mx-13-fire-truck-engine.jpg)

 

## Specifications

| Custom Chassis | Enforcer™, Velocity®, Saber® (Build My Pierce™ Program) | Configuration | Inline 6-cylinder   |
| --- | --- | --- | --- |
| Bore x Stroke (mm) | 130 x 162 | Displacement | 12.9 liters   |
| Dry Weight | 2,600 lb | Oil System Capacity | 42 U.S. quarts   |
| Horsepower | 510 hp   | Peak Torque | 1,850 lb-ft   |
| Governed Speed | 2,200 rpm | Clutch Engagement Torque | 937 lb-ft @ 800 rpm   |
| Warranty | 5-yr / 100,000 miles   |  |  |

## Serviceability

**Easily serviced with extended intervals**

- Over 900 Pierce, Peterbilt and Kenworth service centers in North America
- Service is available at select Pierce dealerships
- 98% retail parts availability from Peterbilt and Kenworth
- Easy-to-access replaceable maintenance parts

![The cab of a fire truck tilted up showing a PACCAR engine.](https://www.piercemfg.com/hs-fs/hubfs/The%20cab%20of%20a%20fire%20truck%20tilted%20up%20showing%20a%20PACCAR%20engine..jpg?width=600&height=400&name=The%20cab%20of%20a%20fire%20truck%20tilted%20up%20showing%20a%20PACCAR%20engine..jpg)

 

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