The 2017 QX70 (essentially a rebadged FX) is a solid luxury crossover built on Nissan's FM platform, but the 5.0L V8 variant suffers from catastrophic cylinder liner wear issues that can grenade the motor, while the 3.7L V6 is far more reliable but shares Nissan's common CVT/transmission cooler weaknesses.
5.0L V8 VK50VE Cylinder Liner Failure (Catastrophic)
Common · high severityTypical onset: 60,000-120,000 mi
Symptoms: Excessive oil consumption (1+ quart per 1,000 miles), White/blue smoke on startup or acceleration, Metallic knocking from bottom end, Loss of compression on multiple cylinders, Check engine light with multiple misfire codes
Fix: Nissan's iron liners separate from the aluminum block causing catastrophic wear. Only real fix is complete engine replacement or full rebuild with aftermarket sleeves. 25-35 hours labor for replacement, 40+ for proper rebuild with re-sleeving.
Estimated cost: $8,000-15,000
Transmission Oil Cooler Failure & Contamination
Common · high severityTypical onset: 80,000-130,000 mi
Symptoms: Transmission slipping or delayed engagement, Milky or strawberry-colored transmission fluid, Overheating transmission, Coolant mixing into ATF creating mayonnaise-like substance, Complete transmission failure if not caught early
Fix: Factory cooler inside the radiator corrodes and allows coolant/ATF cross-contamination. Requires radiator replacement, external trans cooler install, full transmission flush (often multiple times), and sometimes full transmission rebuild if contamination sat too long. 6-8 hours for cooler/flush, add 18-25 hours if trans is damaged.
Estimated cost: $1,200-2,500 (preventive) or $4,500-7,000 (with trans rebuild)
Transmission Mount Collapse
Occasional · medium severityTypical onset: 70,000-110,000 mi
Symptoms: Clunking when shifting from Park to Drive/Reverse, Excessive vibration at idle, Visible sagging of transmission tail, Harsh gear engagement
Fix: Rubber transmission mount deteriorates and allows excessive drivetrain movement. Requires lift access and support of transmission. 2.5-3.5 hours labor.
Estimated cost: $350-600
3.7L VQ37VHR Timing Chain Guide Wear
Occasional · high severityTypical onset: 120,000-160,000 mi
Symptoms: Rattling on cold start that fades after 10-15 seconds, Metallic ticking from front of engine, Check engine light with cam/crank correlation codes, Rough idle or misfires if severely worn
Fix: Primary and secondary timing chain guides wear, especially if oil changes were extended. Requires front cover removal, both timing chains, guides, tensioners, and all related gaskets. 12-16 hours labor. Catch it early before chains jump.
Estimated cost: $2,200-3,500
Fuel Filter/Pump Module Clogging (High-Pressure)
Occasional · medium severityTypical onset: 90,000-140,000 mi
Symptoms: Hard starting especially when hot, Hesitation or stumbling under acceleration, Intermittent stalling, Fuel pressure fluctuations, Check engine light with lean codes or fuel trim issues
Fix: In-tank high-pressure fuel pump strainer clogs or pump itself weakens. Requires fuel tank drop and pump module replacement. Infiniti doesn't sell filter separately—whole module needed. 3-4 hours labor.
Estimated cost: $800-1,400
IPDM-E (Intelligent Power Distribution Module) Failure
Occasional · medium severitySymptoms: Intermittent no-start with no crank, Fuel pump not priming, Random electrical accessories cutting out, Multiple warning lights with no stored codes, Starter relay clicking but no engagement
Fix: Internal relay failures in the engine bay fuse/relay box. Module is $600-900 from dealer and requires programming. 1.5-2 hours labor for replacement and initialization.
Estimated cost: $900-1,300
Buy the 3.7L V6 version only, avoid the 5.0L V8 entirely due to engine grenading issues; budget $2-3k immediately for transmission cooler bypass and fresh fluid if not already done.
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.