2003 INFINITI FX35

Typical onset: 60,000-120,000 mi

Symptoms: Milky or strawberry-colored transmission fluid on dipstick, Coolant level dropping without visible leaks, Transmission slipping or delayed engagement after highway driving, Check engine light with transmission temp codes

Fix: The internal transmission cooler inside the radiator fails, allowing coolant and ATF to mix. This destroys both the transmission and potentially the engine. Requires radiator replacement with external cooler bypass, full transmission fluid flush (multiple cycles), and often transmission rebuild or replacement if caught late. 8-12 hours labor for radiator and flush, add 16-24 hours if transmission needs rebuild.

Estimated cost: $1,200-$6,500

Typical onset: 80,000-150,000 mi

Symptoms: Burning one quart or more per 1,000 miles, Blue smoke on cold start or deceleration, Fouled spark plugs on cylinders 2, 4, or 6, Loss of power and rough idle as rings collapse

Fix: The VQ35DE in this generation develops excessive oil consumption due to piston ring land wear and oil control ring failure. Initially manageable with frequent top-offs, but progresses to catastrophic failure if run low on oil. Proper fix requires engine removal, complete teardown, new pistons, rings, honing, and often head work. 28-35 hours labor for full rebuild, or 18-22 hours for short block replacement.

Estimated cost: $4,500-$8,000

Typical onset: 70,000-110,000 mi

Symptoms: Clunking when shifting from Park to Drive or Reverse, Vibration at idle that disappears in gear, Visible sagging of transmission when inspected from below, Delayed or harsh 1-2 upshift

Fix: The rear transmission mount is hydraulic-filled and fails frequently, allowing excessive drivetrain movement. This accelerates CV axle wear and creates driveline shudder. Replacement requires subframe lowering or partial drop. 2.5-3.5 hours labor with proper alignment afterward.

Estimated cost: $400-$700

Typical onset: 80,000-130,000 mi

Symptoms: Clunking over bumps from front suspension, Wandering or vague steering feel, Uneven inner tire wear, Vibration through steering wheel at highway speeds

Fix: The front lower control arm bushings deteriorate and separate, causing alignment issues and poor handling. Infiniti does not sell bushings separately—requires complete control arm assemblies. Both sides should be done together along with alignment. 3-4 hours labor for both sides.

Estimated cost: $800-$1,400

Typical onset: 90,000-140,000 mi

Symptoms: Fuel gauge reading erratically or stuck at full/empty, Hesitation or stumbling during acceleration, No-start condition with whining noise from tank area, Check engine light with lean codes

Fix: The in-tank fuel pump assembly fails, often starting with sender issues before pump death. Requires fuel tank drop and complete pump module replacement. Fuel system cleaning recommended if contamination present. 3-4 hours labor.

Estimated cost: $600-$1,100

Typical onset: 60,000-100,000 mi

Symptoms: Pulling to one side during braking, One front wheel noticeably hotter after driving, Premature pad wear on one side, Grinding or dragging noise from front corner

Fix: Front brake calipers develop sticking slide pins or piston seals, causing uneven braking and rapid pad consumption. Affected caliper should be replaced, not rebuilt, due to Akebono caliper bore corrosion issues. Replace in pairs for consistent braking. 2-3 hours labor for both sides with pad replacement and fluid flush.

Estimated cost: $700-$1,200

Typical onset: 100,000-150,000 mi

Symptoms: Coolant dripping from passenger side of radiator, Overheating at idle or in traffic, Sweet smell from engine bay, Coolant level slowly dropping

Fix: The plastic side tanks on the radiator crack at the crimped joint, especially on the passenger side. Even if not leaking yet, replace preemptively when doing transmission cooler repair—this radiator design is the root cause of the transmission cooler failure epidemic. Install aftermarket radiator with external transmission cooler. 3-4 hours labor.

Estimated cost: $500-$900