2011 INFINITI FX37

Typical onset: 80,000-140,000 mi

Symptoms: Transmission fluid in coolant (strawberry milkshake appearance in overflow tank), Coolant in transmission (burnt smell, slipping, delayed engagement), Overheating transmission or engine, Complete transmission failure if coolant gets into valve body

Fix: The internal oil cooler in the radiator fails, allowing coolant and ATF to mix. Must replace radiator, flush both systems thoroughly, replace transmission fluid and filter. If contamination reached transmission internals, full rebuild or replacement required (12-16 hours for trans R&R plus rebuild time). Preventive external trans cooler install adds 2-3 hours.

Estimated cost: $1,200-2,500 for radiator/flush only; $4,500-7,000 if transmission rebuild needed

Typical onset: 90,000-130,000 mi

Symptoms: Limp mode (stuck in third gear), No gear engagement at all, Hard shifts or erratic shift points, P0700, P0868, P17F0 codes

Fix: TCM is integral to the valve body inside the transmission pan. Requires pan removal, valve body disassembly, and TCM replacement with reprogramming. Parts are dealer-only and expensive. 4-6 hours labor.

Estimated cost: $1,800-3,200

Typical onset: 120,000-180,000 mi

Symptoms: Cold-start rattle for 2-5 seconds (timing chain slap), Check engine light with P0011, P0021 (cam correlation codes), Loss of power, rough idle, Catastrophic engine failure if chain jumps timing

Fix: VQ37 uses three chains (two primary, one secondary). Stretched chains and worn guides require removal of front covers, water pump, and all timing components. Both banks must be done simultaneously. Includes VVT actuators, tensioners, guides. 14-18 hours labor if caught early; engine rebuild (40+ hours) if chain jumped and bent valves.

Estimated cost: $3,500-5,500 for timing service; $8,000-12,000+ for engine rebuild

Typical onset: 70,000-110,000 mi

Symptoms: Clunk on takeoff or deceleration, Vibration under acceleration, Transfer case fluid leak from front seal, AWD warning light in severe cases

Fix: The front output shaft bushing in the transfer case wears, causing play and eventual seal failure. Requires transfer case removal, disassembly, bushing and seal replacement. 6-8 hours labor. Some shops replace entire transfer case if internal wear is severe.

Estimated cost: $1,200-2,200 for bushing/seal; $2,800-4,000 for used transfer case replacement

Typical onset: 100,000-150,000 mi

Symptoms: Flare on 2-3 or 3-4 upshift (RPM spike between gears), Delayed engagement into Drive or Reverse, Soft or slipping shifts, Transmission may work fine when cold, worse when hot

Fix: Aluminum valve body bores wear, causing pressure loss. Requires valve body removal, machining or replacement, new solenoids and gaskets. 8-10 hours labor. Oversize sleeve kits available but not all shops are equipped for this repair.

Estimated cost: $1,800-3,500

Typical onset: 90,000-140,000 mi

Symptoms: Fuel gauge reads empty or erratic when tank is full, Gauge jumps around while driving, Occasional no-start if pump fails (rare), Check engine light with P0463 (fuel level sensor)

Fix: Sender unit in the tank fails. Requires fuel tank drop, pump module replacement. 3-4 hours labor. Pumps rarely fail, usually just the sender.

Estimated cost: $600-1,100

Typical onset: 80,000-120,000 mi

Symptoms: Clunk or knock over bumps in steering column area, Steering feels loose or has play at center, No fluid leak, power steering works fine

Fix: Rubber bushings at rack mounting points deteriorate. Bushings can be replaced without removing entire rack. 2-3 hours labor. Some techs replace entire rack if internal wear is present, but bushings alone usually solve the clunk.

Estimated cost: $400-800 for bushings; $1,200-1,800 for rack replacement