About the Nissan Frontier Engine

This is the QR25DE, a robust 2.5-liter DOHC inline-four used in the Frontier from 2005, as the live page describes. It carries cast steel connecting rods, a durable steel timing chain, dual counter-rotating balance shafts for smoothness, and an aluminum block and head for light weight and good heat control. Multi-point EFI, coil-on-plug ignition, electronic throttle control, and CVTC on the intake cam round out a service-friendly engine with strong low-end torque for truck duty. It sits longitudinally and is compatible with both manual and automatic transmissions.

Why Frontier Owners Replace the Engine

High mileage, oil consumption, overheating, and timing-related wear are the usual reasons. A healthy QR25DE restores steady low-end torque for towing and hauling, brings back a quiet, low-vibration idle thanks to the balance shafts, and returns the dependable everyday response the Frontier is built on, with the engine inspected for compression before it ships.

Things to Confirm Before Ordering

• Your engine, confirmed by VIN; this is the 2.5L four-cylinder, and per the live FAQ it does not replace the 4.0L V6
• Your transmission match: the four-cylinder used different transmissions than the V6, so the engine-and-transmission pairing should be VIN-confirmed
• Your maintenance plan: per the live FAQ, strict 5,000-mile oil changes, regular timing-chain checks, and prompt air and fuel filter replacement prevent QR25DE failures

What Is Included, What Is Not Included

Vehicle Compatibility

Fitment Assistance

Call (240) 301-0095 with your VIN. Because the Frontier was sold with a four-cylinder and a V6 that used different transmissions, we confirm your engine and the transmission pairing before the engine ships.

Condition and Inspection

This is a used engine, inspected before shipping:

• Compression checked across cylinders
• Timing chain and cover inspected
• External surfaces checked for oil and coolant leaks
• Block and head castings verified OE
• Photos provided before purchase

Why Buy from Us

• Engine clarity: the 2.5L four-cylinder, not the 4.0L V6
• Engine and transmission pairing confirmed by VIN
• Compression and timing chain inspected before sale
• Free shipping to all 50 states, no hidden fees
• No core charge, keep your old engine
• 15 day replacement warranty