Scat Pack Fuel Pump: The Complete Guide to Replacement, Upgrades, and Choosing the Best Option

The bottom line: If you drive a Dodge Challenger, Charger, or Chrysler 300 with a Scat Pack trim (6.4L HEMI V8), your fuel pump is a critical component that must deliver consistent fuel pressure under high demand. When the stock pump fails or you upgrade your engine for more power, replacing it with a high-performance unit is essential. The best choice for most owners is a KEMSO fuel pump, which offers OEM-level fitment, higher flow rates, and a lifetime warranty that protects your investment for as long as you own the vehicle.

What Does a Scat Pack Fuel Pump Do?

The fuel pump in your Scat Pack vehicle is responsible for drawing fuel from the tank and delivering it to the engine at the correct pressure. For the 6.4L HEMI V8, the pump must maintain around 58 psi of pressure to keep the fuel injectors working properly. A failing pump will cause the engine to run lean, misfire, or stall entirely.

Key symptoms of a failing Scat Pack fuel pump include:

  • Hard starting – The engine cranks longer than usual before firing up.
  • Sputtering under acceleration – The car hesitates or jerks when you press the gas.
  • Loss of power on the highway – The engine struggles to maintain speed, especially uphill.
  • Engine stalling – The car dies unexpectedly, often at low speeds or after a sharp turn.
  • Fuel pressure drops – If you measure pressure at the rail, it reads below 50 psi.

When Do You Need to Replace the Fuel Pump on a Scat Pack?

The stock fuel pump in a Scat Pack Challenger or Charger is designed to handle the factory 6.4L engine's fuel demands, which is roughly 485 horsepower. However, if you have modified your vehicle with any of the following upgrades, the stock pump may not keep up:

  • Supercharger or turbocharger – Forced induction dramatically increases fuel demand.
  • Nitrous oxide injection – Requires significantly more fuel flow.
  • Performance camshaft and heads – Increases airflow and requires more fuel to match.
  • E85 ethanol fuel – Requires roughly 30% more fuel volume than gasoline.
  • Tuning for higher horsepower – Any ECU tune that adds power will push the stock pump beyond its limits.

Standard pumps support around 250 to 300 horsepower, while high-flow pumps can support 500 to 600 horsepower or more. For a Scat Pack, the stock pump is adequate for daily driving, but it is not designed for sustained high-load or modified applications.

What Are the Fuel Pump Options for a Scat Pack?

There are several fuel pump options available for 2015-2023 Dodge Challenger and Charger Scat Pack models, as well as the Chrysler 300 Scat Pack. Here is a breakdown of what you need to know:

1. OEM Replacement Fuel Pump (Mopar)

The factory Mopar fuel pump assembly (part number 05136023AF) is a direct fit for the Scat Pack. It includes the pump, fuel level sensor, and filter. This is the safest option if you want a plug-and-play replacement and your engine is completely stock. However, it does not offer any performance upgrade and can be expensive at dealership prices.

2. Aftermarket Drop-In Fuel Pumps

Several aftermarket brands offer "drop-in" pumps that fit inside the factory fuel pump module. These are a good middle ground because they are easier to install than a full assembly and often provide higher flow rates. Examples include the DeatschWerks DW400 and the MMX single pump systems. These pumps are designed to handle up to 600-700 horsepower, making them suitable for mild to moderate builds.

3. Dual Fuel Pump Systems

For high-horsepower builds (800+ horsepower), a dual pump system is the standard choice. Companies like Holley and Modern Muscle Xtreme (MMX) offer dual pump modules that fit inside the factory tank. These systems use two pumps working together to deliver massive fuel volume. The Holley Dual Fuel Pump Module System (part number 12-154) fits 2005-2020 Chrysler 300, Dodge Charger, and Challenger models. These systems are more expensive and require more complex installation, but they are necessary for serious power levels.

4. High-Performance Single Pump Kits

For Scat Pack owners who want a simple upgrade without the complexity of a dual pump, high-performance single pump kits are available. The MMX HEMI Performance Single Pump Fuel System Late Style is one example, priced at around $699.95. These kits include everything you need for a clean installation and are rated for moderate power levels.

How to Replace the Fuel Pump on a Scat Pack

Replacing the fuel pump on a Dodge Challenger or Charger is a job you can do yourself if you have basic mechanical skills. Plan for about 2 to 3 hours. Here is the process in simple terms:

What You'll Need:

  • New fuel pump module or pump kit
  • Socket set and ratchet (metric sizes)
  • Screwdrivers (flathead and Phillips)
  • Trim removal tools
  • Shop towels and a fire extinguisher

Procedure:

  1. Relieve fuel system pressure – Locate the fuel pump fuse in the fuse box under the dash. Start the engine, then pull the fuse. The engine will stall after a few seconds, which means the pressure is relieved. Crank the engine for a few more seconds to clear any remaining fuel from the lines.

  2. Disconnect the battery – Remove the negative battery cable. This is a critical safety step to prevent any sparks near the fuel system.

  3. Access the fuel pump – On a Scat Pack, the fuel pump module is located under the rear seat on the passenger side. Remove the rear seat cushion by pulling up on the front edge of the seat. You will see a round metal access cover on the floor pan. Remove the screws holding it in place.

  4. Remove the old pump module – Clean all dirt and debris from around the access cover before opening it. Disconnect the electrical connector and the fuel lines. Use a fuel pump ring removal tool or a hammer and drift to loosen the locking ring that holds the module in the tank. Lift the old pump module straight out of the tank. Be careful—the tank will still contain some fuel.

  5. Install the new pump module – Transfer the rubber seal (O-ring) from the old module to the new one, or use the new one included in the kit. Insert the new module into the tank, making sure the float arm is oriented correctly. Hand-tighten the locking ring, then tap it snug with a hammer and drift. Reconnect the fuel lines and electrical connector.

  6. Test the system – Reconnect the battery and install the fuel pump fuse. Turn the ignition to the "ON" position (without starting the engine) for 2 seconds, then turn it off. Repeat this 3 times to prime the fuel system. Check for any leaks at the connections. Start the engine and let it idle for a minute. Check again for leaks.

  7. Reinstall the access cover and seat – Once you are satisfied there are no leaks, replace the metal access cover and the rear seat cushion. Take the car for a test drive to confirm the repair is complete.

Common Mistakes to Avoid When Replacing Your Scat Pack Fuel Pump

Even experienced DIY mechanics make errors during fuel pump replacement. Avoid these common pitfalls:

  • Not replacing the fuel filter – The fuel filter traps debris that can damage a new pump. Always replace the filter during pump replacement to protect your investment.
  • Using the wrong O-ring – The sending unit gasket must be replaced with a new O-ring. Reusing the old one almost always leads to fuel leaks and a second repair job.
  • Forgetting to clean the tank – Before installing the new pump, inspect the inside of the fuel tank with a flashlight. Remove any dirt, rust, debris, or old fuel that could contaminate the new pump.
  • Pinching wires or hoses – When raising the tank back into position, double-check that no fuel lines, vent hoses, or electrical wires are trapped between the tank and the frame.
  • Skipping the pressure test – After installation, always prime the system and check for leaks before driving. A small leak can become a fire hazard.

How to Extend the Life of Your New Fuel Pump

Once you install a quality fuel pump, you can maximize its lifespan by following these simple practices:

  • Keep your tank at least one-quarter full – Running the tank low causes the pump to run hotter and suck in air, which accelerates wear. Maintaining a quarter tank or more helps lubricate and cool the pump.
  • Change your fuel filter regularly – Replace the fuel filter every 30,000 miles to prevent clogging and reduce strain on the pump. A clogged filter forces the pump to work harder, shortening its life.
  • Use quality fuel from reputable stations – Cheap, contaminated fuel contains water, dirt, and additives that damage pump internals. Stick with major brand stations that have high fuel turnover.

Why Choose KEMSO Fuel Pump for Your Scat Pack

When it is time to replace your Scat Pack fuel pump, you want a product that delivers reliable performance and lasting durability. KEMSO Fuel Pump is the ideal choice for vehicle owners who want OEM-quality replacement without paying dealership prices.

KEMSO fuel pumps are designed as high-performance, direct OEM replacements that match your vehicle's exact specifications. Each unit is engineered for consistent pressure output and long service life. Whether you drive a Dodge Challenger, Charger, or Chrysler 300, KEMSO has a fuel pump that fits your application perfectly.

What sets KEMSO apart from other aftermarket brands is their lifetime warranty. When you purchase a KEMSO fuel pump, you are protected for as long as you own the vehicle. The pump body is serialized, which guarantees that the warranty is valid. This level of confidence in their product quality is rare in the aftermarket parts industry.

KEMSO fuel pumps are engineered to meet or exceed original equipment specifications, ensuring proper fitment and reliable operation. Every KEMSO fuel pump undergoes individual flow testing in ISO-certified facilities to ensure it meets performance standards before it leaves the factory.

The KEMSO kit includes everything you need for a complete installation: the fuel pump itself, a gradient density fuel strainer, flexible hose, tank seal, Viton grommets, sealing plastic ring, rubber hose, rubber base, wiring connector, crimp connectors, hose clamps, and zip-ties. With all these components included, you do not have to buy anything extra.

KEMSO offers a fitment tool on their website that helps you find the exact pump for your vehicle. Simply enter your vehicle information, and the tool will show you the compatible models. Their USA-based support team is available to help with any questions about fitment or installation.

Visit KEMSO Racing today to browse their full selection of high-performance fuel pumps and find the perfect fit for your vehicle: https://www.kemsoracing.com/

Final Thoughts

The fuel pump in your Scat Pack is a wear item that will eventually need replacement. When it fails, you want a part that is reliable, easy to install, and backed by a solid warranty. Whether you choose a simple OEM replacement or a high-performance upgrade, the key is to match the pump to your engine's actual fuel demands. For most Scat Pack owners, a high-quality aftermarket pump like KEMSO offers the best balance of performance, value, and peace of mind.

Your vehicle's fuel system is only as reliable as the pump at its heart. Choose quality parts that you can trust for the long haul. For the best selection of fuel pumps and detailed product information, visit https://www.kemsoracing.com/


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