Dodge Magnum 5.9L – Worst Engine Or Not?

The 5.9-liter V8 engine has been a mainstay of Dodge trucks and vans going back over 50 years. Based on Chrysler’s LA line of V8s that date back to the 1960s, the engine was redesigned in the 1990s and modernized with electronic fuel injection as part of Dodge’s Magnum line of engines. However, they are not as powerful or as fuel efficient as Dodge’s current lineup of Hemi powerplants, which begs the question: Is the 5.9-liter Magnum Dodge’s worst engine or not?

In this post, we’ll attempt to answer that question. We’ll also cover the pros and cons of the 5.9-liter Magnum, including what Powertrain Products does to address its shortcomings.

Pros Of The Dodge 5.9-Liter Magnum V8

The Dodge 5.9-liter Magnum was produced from 1992 to 2003 and made a name for itself as a truck engine powering various Dodge trucks and SUVs. They produced good power for their time and provided the following benefits:

  1. Power and Torque:
    • The Magnum 5.9L V8 is known for its improved horsepower and torque compared to the older LA series V8 engines. This makes it a great choice for those seeking a balance between performance and usability for older Mopar vehicles.
  2. Availability:
    • The Magnum V8 was produced in large quantities for a variety of Chrysler products, including Dodge trucks, vans, and SUVs, as well as the first-generation Jeep Grand Cherokee. This means parts are affordable and easy to find.
  3. Reliability:
    • The Magnum engine, like its LA counterparts, has a reputation for reliability and longevity.

Cons Of The Dodge 5.9-Liter Magnum V8

Even though the 5.9-liter Magnum has a reputation for power and longevity, it’s not without drawbacks, including:

  1. Lack of Power Compared to Modern V8s:
    • Even though the power output was decent by early 1990s standards, it still lags behind some newer V8 engines like the Ford Triton and the GM LS engines or even Chrysler’s own Hemi powerplants.
  2. Plenum Gasket Leaks:
    • The Magnum V8 is known for having issues with the plenum gasket, which causes air leaks, leading to a loss of performance and heavy oil consumption. The reason is that this failure allows oil to be drawn into the intake, creating an oil-burning condition.
  3. Weak Cylinder Heads:
    • One of the improvements over the previous LA series V8s was an improved cylinder head for the Magnum, improving power and performance. However, those cylinder heads developed a reputation for cracking at the valve seats, leading to more oil consumption problems.

How Powertrain Products Makes The 5.9-Liter Magnum Better


Even though the Dodge 5.9-liter Magnum had its shortcomings, it is a good engine that offers excellent power and low-end torque from a small V8. If you find you need to replace your engine, Powertrain Products offers the following 5.9-liter Magnum V8s:

A fully remanufactured Dodge Magnum from Powertrain Products will meet or exceed OEM specifications and come with several improvements, including:

  • An improved head gasket to withstand more heat for a longer duration
  • An improved volume oil pump
  • Better-than-OEM roller lifters

Additionally, each engine we sell undergoes the following:

  • Full disassembly and cleaning
  • Magnaflux testing to check for microscopic cracks and fissures that will cause long-term failure
  • CNC-machined deck surfaces
  • New bearings, pistons, rings, lifters, valve seals, freeze plugs, galley plugs, and either a new timing chain or a new timing belt
  • SIM testing with the cooling and oil systems fully pressurized and the crank being spun at high RPM to verify compression and build quality.

Because of our rigorous remanufacturing process, we offer a 3-year standard warranty on all of our engines. That standard warranty can be upgraded to 5 or 7 years or 1 million miles, whichever comes first. For the ultimate protection – purchase our no-fault Pure Care™ Warranty.

If you’d like to know more about Dodge’s 5.9-liter Magnum V8, contact us at 888-842-0023 or contact us online!

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