The spark plugs you’ll need depend on which engine your 2015 Altima uses. The 2.5-liter four‑cylinder and the 3.5-liter V6 have different plug specifications, so you should confirm the exact OEM type for your car’s VIN.
Engine options in the 2015 Altima
The 2015 Altima was offered with two engines across trims: a 2.5-liter four-cylinder and a 3.5-liter V6. Because spark plug specifications are tied to the engine design, the correct plugs must match the engine rather than the model year alone. When selecting replacements, opting for Nissan OEM plugs or equivalents from reputable brands (such as NGK or Denso) that match the factory heat range and thread size is important.
- 2.5-liter four-cylinder (QR25DE): uses plugs that conform to the OEM heat range and thread size; aftermarket replacements are typically available in platinum- or iridium-tipped designs that meet the factory specs.
- 3.5-liter V6 (VQ35DE): uses plugs that conform to the OEM heat range and thread size; iridium-tipped plugs are commonly used in this engine family, with NGK or Denso equivalents that match the factory specifications.
For exact part numbers, gaps, and torque specifications, consult your vehicle’s VIN-specific Nissan parts catalog or the owner's manual, and confirm with a dealership or trusted mechanic before purchasing.
How to source the right plugs and ensure a proper fit
To avoid wrong parts, follow a sourcing checklist and installation notes designed for the Altima. This approach reduces the risk of mis-sizing and ensures optimal engine performance.
- Verify engine version and VIN. The Altima's engine type determines the spark plug recommendation; the VIN helps confirm the exact specification from Nissan or a trusted aftermarket supplier.
- Prefer OEM or OEM-equivalent plugs from known brands (NGK, Denso). Ensure the heat range, thread size, and reach match the factory specification.
- Follow Nissan's torque spec and recommended gap when installing plugs to ensure proper ignition and sealing.
With the right plugs and careful installation, the Altima’s ignition system should maintain strong starting performance and efficient combustion.
Summary: The 2015 Nissan Altima uses two different spark plug types depending on engine: the 2.5L four-cylinder and the 3.5L V6 each require plugs that match their OEM specifications. Always confirm exact part numbers and gaps via VIN or the owner’s manual, and consider OEM or OEM-equivalent plugs from NGK or Denso for best results. Regular inspection and proper installation are essential for performance and longevity.