In most Nissan applications, a 2.5-liter engine refers to a four-cylinder powerplant (the QR25DE). There are rare exceptions with a 2.5-liter V6 (the VQ25DE) used in some older models. This article explains how to tell which engine you have and what to look for when you see a “2.5” designation.
What the 2.5-liter label usually means
The 2.5-liter designation is a measure of displacement, not a guarantee of cylinder count. For Nissan, the most common 2.5L engine is an inline-4 (a four-cylinder) in mainstream models sold in recent years.
- QR25DE — 2.5 L inline-4 (four cylinders). This engine has powered many Nissan cars and crossovers, including typical configurations found in Altima, Rogue, Sentra, and X-Trail models.
In rare cases, a 2.5-liter V6 has appeared in Nissan/Infiniti lineups in the past, which would be a six-cylinder configuration. The presence of a V6 at 2.5 L is not common in modern Nissan consumer vehicles.
Are there 2.5-liter Nissan engines that are not four cylinders?
Yes. There is a 2.5 L V6 known by the VQ25DE designation that has appeared in a limited set of older Nissan/Infiniti applications. This variant is relatively uncommon compared to the widespread 2.5 L inline-4 QR25DE found in most current Nissan models. When shopping or diagnosing a vehicle, the engine code is the surest way to confirm cylinder count.
- VQ25DE — 2.5 L V6 (six cylinders). This configuration appears in a smaller number of older Nissan/Infiniti models.
Engine code and model year are your best clues if you want to know exactly how many cylinders your 2.5-liter Nissan engine has.
How to confirm the exact engine in your Nissan
Before checking your car, use these steps to verify the engine type and cylinder count accurately.
- Locate the engine code stamped on the engine block or near the valve cover, which identifies the family (QR25DE, VQ25DE, etc.).
- Check the vehicle identification number (VIN) decoder or the in-cabin door placard for the engine code associated with your car’s build.
- Consult the owner’s manual or the official Nissan service information for your model/year to cross-check the engine designation.
- When in doubt, contact a Nissan dealer or a certified mechanic who can read the exact engine code from the ECU or factory documents.
Verifying the engine code is the most reliable way to determine whether your 2.5-liter Nissan is a four-cylinder or a six-cylinder variant.
Summary
For most buyers and owners, a 2.5-liter Nissan engine is a four-cylinder (QR25DE) used across a broad range of models. A minority of older or Japan-market configurations employed a 2.5-liter V6 (VQ25DE), which carries six cylinders. Always confirm the engine code on the block or through the VIN to be certain about cylinder count and maintenance needs.