The 5.2-liter Dodge engine is the same V8 as the 318 cubic-inch motor, simply labeled in liters instead of cubic inches. In Mopar naming, 5.2 L and 318 cu in refer to the same displacement, just expressed differently.
To understand how Mopar labels its engines, you need to know how displacement is measured, which engine family a motor belongs to, and how those labels have evolved over time. This article breaks down the relationship between the 5.2 and the 318, and what to look for when identifying one in a Dodge or Jeep vehicle.
Displacement and naming: what the numbers mean
Before diving into specifics, here is how Mopar typically uses displacement numbers to name engines:
- 5.2 L equals 318 cubic inches. The 5.2 designation is the engine’s displacement in liters, and 318 is the same displacement expressed in cubic inches.
- The 5.2 is associated with the modern Magnum small-block V8, which evolved from the older LA family. The same basic engine block lineage carries the 318 label in older Mopar catalogs.
- Historically, “318” referred to an older LA-engine family, while “5.2” is a contemporary metric-based label used for the same or improved versions of that engine architecture.
- In everyday use, vehicles that carry a 5.2/318 badge are often Dodge Ram pickups, Durango, Grand Cherokee, and other Dodge/Chrysler products from the 1990s into the early 2000s, though the exact applications vary by year and market.
In short, the 5.2 and the 318 denote the same engine displacement, just coming from different naming conventions that Mopar has used over the years. The engine has seen updates across generations, but the fundamental size remains the same.
Verifying a 5.2/318 in your vehicle
If you want to confirm whether a given Dodge motor is the 5.2 Magnum/318, use these checks commonly available to enthusiasts and technicians:
- Look for the engine displacement stamp on the engine block or valve cover that explicitly lists “5.2 L” or “318.”
- Check the engine family designation (such as Magnum) on the valve covers, intake manifold, or the deck stamping; Magnum engines are the modern evolution of the 318 family.
- Consult the vehicle’s VIN or door jamb sticker to identify the engine option listed for that VIN, which will indicate displacement and engine family.
These checks typically suffice for most owners to confirm whether a motor labeled “5.2” is the same as the classic 318 cubic-inch V8.
Summary
Yes — a 5.2 Dodge motor is the same engine as the 318 cubic-inch V8. The difference lies in labeling: “5.2 L” is the metric, modern designation, while “318 cu in” is the traditional cubic-inch measurement. The 5.2 Magnum family represents the continued evolution of the same underlying small-block architecture that started as the LA series, and it has powered a wide range of Dodge and Chrysler vehicles over the years.