The 2019 NP300 is Nissan's global-market workhorse truck, sold primarily outside North America. The QR25DE gas engine is generally reliable, but the YS23 diesel and its peripheral systems—particularly the cooling and timing chain components—are where you'll see problems stack up past 60,000 miles.
Timing Chain Stretch and Guide Failure (YS23 Diesel)
Common · high severityTypical onset: 60,000-100,000 mi
Symptoms: Cold-start rattle lasting 5-10 seconds, Check engine light with cam/crank correlation codes (P0016, P0017), Loss of power under load, Metal shavings in oil during changes
Fix: Full timing chain kit replacement including guides, tensioners, and both camshaft sprockets. Requires front cover removal and cam timing reset. 8-12 labor hours depending on collateral damage inspection.
Estimated cost: $1,800-3,200
Transmission Oil Cooler Line Corrosion and Leaks
Common · medium severityTypical onset: 70,000-120,000 mi
Symptoms: Transmission fluid puddles under front of vehicle, Burnt transmission smell after highway driving, Erratic shifting when fluid level drops, Pink or red fluid visible on radiator support brackets
Fix: Replace corroded steel cooler lines with OEM or aftermarket braided hoses. Often coincides with radiator replacement if internal ATF/coolant contamination suspected. 3-5 hours labor if just lines, 6-8 if radiator included.
Estimated cost: $600-1,400
Lifter Collapse and Camshaft Wear (YS23 Diesel)
Occasional · high severityTypical onset: 80,000-150,000 mi
Symptoms: Persistent ticking or tapping noise from valve cover area, Loss of compression in one or more cylinders, Rough idle that worsens when warm, Metal debris in oil filter during service
Fix: Replace all lifters/tappets and inspect camshaft lobes for scoring. If cam is damaged, full head R&R required. Cylinder head resurfacing common. 12-18 hours labor for complete job with head work.
Estimated cost: $3,500-6,000
Head Gasket Failure (YS23 Diesel)
Occasional · high severityTypical onset: 90,000-140,000 mi
Symptoms: White smoke from exhaust on cold start, Coolant loss with no visible external leaks, Overheating under load or towing, Milky oil on dipstick or oil cap, Bubbles in coolant reservoir when running
Fix: Head gasket replacement with head removed, pressure tested, and resurfaced. Always inspect for cracked head. Timing components typically replaced during same job. 14-18 hours labor.
Estimated cost: $2,800-4,500
Harmonic Balancer Deterioration (Both Engines)
Occasional · medium severityTypical onset: 100,000-150,000 mi
Symptoms: Vibration at idle that increases with RPM, Serpentine belt misalignment or unusual wear, Visible rubber ring separation on balancer pulley, Squealing or chirping from front of engine
Fix: Replace harmonic balancer with OEM or quality aftermarket unit. Requires special puller and installer tools. Inspect crankshaft snout for damage. 2-3 hours labor.
Estimated cost: $400-700
Transmission Mount Collapse
Common · low severityTypical onset: 60,000-100,000 mi
Symptoms: Clunking when shifting from park to drive or reverse, Excessive vibration through floor and shifter, Visible sagging of transmission when inspected on lift, Harsh engagement into gear when cold
Fix: Replace worn transmission mount and crossmember bushings. Transmission must be supported during R&R. 1.5-2.5 hours labor.
Estimated cost: $250-450
Buy a gas QR25DE model if you can find one—diesel YS23 engines are maintenance-intensive and expensive to repair once timing or valvetrain issues start, which they will.
AI-assisted summary drawn from NHTSA recall data, our labor-times database, and platform knowledge. Not a substitute for a pre-purchase inspection on a specific vehicle.