The Nissan Altima 2.5 uses a four-cylinder engine—the 2.5-liter inline-four that powers most of the Altima lineup in recent years. The “2.5” designation refers to displacement, not the number of cylinders, and in this case it points to a four-cylinder powerplant. While Altima models have offered a V6 option in older generations and, in some years, a 2.0-liter turbo four in higher trims, the 2.5 variant remains a four-cylinder engine.
What does “2.5” refer to?
In modern Nissan nomenclature, the number after the model name typically signals engine displacement. For the Altima 2.5, 2.5 liters corresponds to a four-cylinder inline configuration. The engine family used across these cars is designed for a balance of efficiency and usable power rather than high-end performance.
Engine layout and configuration
The 2.5 engine in the Altima is an inline-four (I4) configuration. It is usually paired with a continuously variable transmission (CVT) in most trims, a setup chosen to maximize fuel economy in a midsize sedan.
Other engine options in the Altima lineup
While the 2.5 is a four-cylinder engine, the Altima has offered other powerplants in various model years. A V6 option (3.5L) appeared in older generations, providing more horsepower for buyers seeking performance. More recently, Nissan introduced a 2.0-liter turbocharged four-cylinder (VC-Turbo) on certain trims for higher output, though this remains a separate option from the 2.5L.
But the 2.5 remains the standard four-cylinder option
Across most current and recent model years sold in the United States, the Altima 2.5 is defined by its four-cylinder 2.5L engine. The choice between the 2.5 and other engines depends on what balance of efficiency, cost, and performance you want.
Performance and maintenance implications
As a four-cylinder engine, the Altima 2.5 emphasizes efficiency and tractable everyday performance. Expect typical four-cylinder maintenance patterns: routine oil changes every 5,000–7,500 miles depending on oil and driving conditions, along with standard inspections of belts, plugs, and the cooling system. Reliability for the 2.5 inline-four has generally been solid when serviced on schedule, though real-world results depend on maintenance history and model year.
Summary
Final word: Nissan Altima 2.5 is a four-cylinder engine. The 2.5 designation refers to displacement, not to six cylinders. If you’re shopping for an Altima and want more power, you may consider other engines that Nissan has offered in certain years, such as a V6 or a turbocharged four-cylinder, but the 2.5 model itself remains a four-cylinder powerplant.