2013 INFINITI M56

Typical onset: 60,000-120,000 mi

Symptoms: Sudden loss of oil pressure with no external leaks, Rod knock or bearing noise appearing rapidly after oil pressure drop, Check engine light with low oil pressure codes (P0524), Metal shavings in oil during changes, Engine seizure in worst cases

Fix: The internal oil gallery gaskets (part of the timing cover assembly) fail and starve the timing chain tensioners and main bearings. Requires complete engine teardown or replacement. If caught early (pressure drop only), timing cover replacement runs 18-22 hours labor. Most cases discovered after bearing damage require short block or complete engine—35-45 hours for R&R plus machine work. Many owners opt for used/reman engines.

Estimated cost: $8,000-15,000

Typical onset: 70,000-110,000 mi

Symptoms: Transmission fluid puddles under vehicle, Burnt transmission fluid smell, Slipping or delayed shifts when fluid is low, Pink fluid visible near radiator or under engine bay

Fix: The 7-speed automatic's external cooler lines corrode at fittings, and the auxiliary cooler develops pinhole leaks. Cooler line replacement is 2-3 hours; full external cooler replacement adds another 2 hours. Requires transmission fluid flush after repair. Catch it early before running the trans low on fluid.

Estimated cost: $800-1,800

Typical onset: 80,000-130,000 mi

Symptoms: Clunking or vibration during acceleration from a stop, Rumbling or droning noise at highway speeds, Vibration felt through the floor at 40-60 mph, Noise changes with throttle input

Fix: The two-piece driveshaft's center support bearing and flex disc wear out. Infiniti often recommends replacing the entire driveshaft assembly (4-5 hours labor), though some shops rebuild with aftermarket bearings for less. Covered by NHTSA recall for certain VINs—check recall status first. Failure can damage the tunnel or trans tailshaft if ignored.

Estimated cost: $600-1,400

Typical onset: 60,000-100,000 mi

Symptoms: Clunk when shifting from Park to Drive or Reverse, Excessive vibration at idle in gear, Visible sagging or movement of transmission when inspected on lift

Fix: Rubber transmission mounts collapse and the rear crossmember mounting points crack from the weight of the 7-speed. Requires transmission support during replacement—2.5-4 hours depending on which mounts are shot. OEM mounts are expensive; aftermarket options exist but quality varies.

Estimated cost: $500-1,000

Typical onset: 90,000-140,000 mi

Symptoms: Extended cranking before starting, especially when hot, Rough idle or hesitation under load, Check engine light with fuel pressure/trim codes (P0087, P0191), Sudden stalling in extreme cases

Fix: The direct-injection high-pressure pump (mounted on the engine, driven by camshaft) wears internally or the relief valve sticks. Replacement involves fuel system depressurization and camshaft access—5-7 hours labor. Use OEM or quality reman pump; cheap aftermarket units fail quickly. Covered under powertrain warranty if still applicable.

Estimated cost: $1,500-2,500

Typical onset: 70,000-120,000 mi

Symptoms: Vehicle sags at one corner overnight, Suspension warning light with compressor run-time codes, Hissing noise near struts, Compressor runs constantly when parked

Fix: Models with hydraulic active suspension develop air spring leaks at the bellows or compressor pump failures. Single air spring replacement is 2-3 hours; compressor is 3-4 hours. Many owners convert to conventional coilovers ($2,000-3,000) rather than chase leaks. If keeping active system, replace all four springs at once for longevity.

Estimated cost: $1,200-2,000 per corner; $3,500-5,000 for compressor