What is a 5.4L engine?

A 5.4L engine refers to an internal combustion engine with a total displacement of 5.4 liters. This displacement is the total volume of all the cylinders in the engine. A larger displacement generally means more power, but also usually means less fuel efficiency.

The "5.4L" designation doesn't specify the *type* of engine (e.g., V8, V6, inline-6, etc.) or its other characteristics (e.g., number of valves per cylinder, fuel injection type, etc.). Many different manufacturers have produced 5.4L engines over the years with varying designs. To know more specifics, you'd need to know the manufacturer and model of the vehicle or machine it's in.