2013 INFINITI QX50

Typical onset: 80,000-130,000 mi

Symptoms: Sudden severe oil consumption (1 qt per 500-1000 miles), Low oil pressure warning at idle when hot, Metallic rattling from timing chain area, Blue smoke on startup or acceleration

Fix: Internal oil gallery gaskets fail, starving components and causing bore glazing/ring damage. Requires complete engine teardown, new gallery gaskets, timing components, often pistons/rings or short block if damage progressed. 25-35 labor hours for full internal reseal; 30-40 hours if short block needed.

Estimated cost: $4,500-8,500

Typical onset: 70,000-110,000 mi

Symptoms: Transmission fluid in coolant (strawberry milkshake appearance), Coolant in transmission (delayed engagement, slipping), Erratic shifting or limp mode, Overheating transmission or engine

Fix: Factory cooler integrated into radiator fails, cross-contaminating fluids. Requires radiator replacement, complete transmission flush (often multiple flushes), external cooler addition recommended. If caught late, transmission rebuild needed. 4-6 hours for radiator/flush; add 18-25 hours if transmission damaged.

Estimated cost: $1,200-2,000 (caught early) / $4,500-6,500 (transmission damaged)

Typical onset: 100,000-150,000 mi

Symptoms: Cold-start rattle for 2-5 seconds (chain slap), Metallic whirring or grinding from front of engine, Check engine light with timing correlation codes (P0011, P0021), Loss of power or rough idle

Fix: VQ37 primary and secondary timing chains stretch; guides crack. Requires front cover removal, all three chains, guides, tensioners, VVT solenoids. Preventive job at 100k recommended if rattling present. 12-16 labor hours.

Estimated cost: $2,200-3,500

Typical onset: 60,000-100,000 mi

Symptoms: Clunk or thud during 1-2 or 2-3 upshifts, Vibration at idle in Drive, Driveline lurch when shifting from Park to Drive, Visible sag on driver side of transmission

Fix: Hydraulic transmission mount fails from heat and age. Simple replacement but requires trans support and subframe access. OEM or upgraded polyurethane recommended over cheap aftermarket. 2-3 labor hours.

Estimated cost: $350-600

Typical onset: 90,000-140,000 mi

Symptoms: No-start with crank, no fuel pressure, Intermittent stalling when fuel level below 1/4 tank, Whining or buzzing from rear seat area, Hesitation or stumble under load

Fix: In-tank fuel pump assembly fails (pump motor or level sender). Requires tank drop or rear seat/access panel removal depending on tech preference. 3-4 labor hours.

Estimated cost: $800-1,300

Typical onset: 80,000-120,000 mi

Symptoms: Harsh or delayed 2-3 shift, Limp mode (3rd gear only), Shift flare (RPM spike) between gears, P0745, P0868 codes (pressure control solenoid)

Fix: RE5R05A solenoid block or valve body bores wear, causing pressure loss. Requires pan drop, valve body removal, solenoid replacement or full valve body if bores scored. 6-8 hours labor.

Estimated cost: $1,400-2,200