2021 LINCOLN AVIATOR

Typical onset: 30,000-70,000 mi

Symptoms: Severe knocking or rattling from engine bay, especially on cold starts, White or blue smoke from exhaust under acceleration, Metal shavings in oil during changes, Sudden loss of power or engine misfire codes (P0300-P0306), Check engine light with low compression codes

Fix: Ford's cylinder deactivation system causes bore scoring and piston scuffing. Repair requires complete engine rebuild or replacement—expect 18-24 labor hours for short block swap, more for full rebuild. Many cases covered under powertrain warranty extension through 60k-80k miles, but out-of-warranty failures are financially catastrophic. TSBs exist but don't prevent recurrence.

Estimated cost: $12,000-18,000

Typical onset: 40,000-90,000 mi

Symptoms: Hard starting or extended cranking, especially when hot, Rough idle with fuel trim codes (P0087, P0093), Intermittent stalling at low speeds or during acceleration, Fuel smell in cabin or engine bay, Limp mode activation under load

Fix: The direct-injection HPFP on the 3.0TT fails prematurely, often contaminating the fuel system with metal debris. Requires pump replacement (4-5 hours) plus fuel system flush and potentially injector replacement if contaminated. Critical to replace fuel filter and inspect injectors during repair. Some warranty extensions apply.

Estimated cost: $2,200-4,500

Typical onset: 35,000-80,000 mi

Symptoms: Transmission fluid puddles under vehicle, usually passenger side, Burning smell after driving or when parked, Transmission temperature warning light, Harsh or delayed shifts when fluid is low, Pink or red fluid visible on cooler lines near radiator

Fix: The 10R80 transmission cooler lines develop leaks at crimped connections and where lines pass through frame rails. Early catch requires just line replacement (2-3 hours), but delayed repairs cause transmission damage from low fluid. Replace both lines preventively when one fails. Flush and refill required.

Estimated cost: $800-1,400

Symptoms: "Stop Safely Now" message with powertrain malfunction warning, Rapid battery capacity loss or failure to charge beyond 50-70%, Cooling fan runs constantly even when parked, Battery overheating warnings in hot weather, Electric-only range drops to under 10 miles

Fix: PHEV models suffer cooling system failures in the high-voltage battery pack—blocked coolant passages or failed thermal sensors trigger full battery replacement under recall/warranty. Out-of-warranty cost is devastating. Multiple recalls issued (21S46, 22S33). Repair involves complete HV battery pack R&R, 6-8 hours minimum, often back-ordered for weeks.

Estimated cost: $15,000-22,000

Symptoms: Blank or frozen backup camera screen when in reverse, "Service Rear Park Aid" or "Camera Unavailable" messages, Intermittent or complete loss of 360-degree camera views, False parking sensor alerts or no alerts when objects present, System reboots or glitches after cold starts

Fix: Multiple recalls (21S32, 21V629, others) address camera module software and hardware failures. Requires camera module replacement and software updates (1.5-2 hours). Some cases need complete APIM (infotainment module) replacement. Covered under recalls through ~2024, but post-recall failures still occur requiring module replacement.

Estimated cost: $600-1,200

Typical onset: 50,000-90,000 mi

Symptoms: Clunking or popping noise over bumps from front end, Steering wheel vibration or shimmy at highway speeds, Uneven or accelerated inner tire wear, Vehicle pulls to one side after hitting bumps, Loose or imprecise steering feel

Fix: The independent rear suspension uses rubber bushings that fail early on the heavy Aviator platform, especially on PHEV models. Requires control arm replacement (bushings not sold separately), 2.5-3 hours per side. Always do alignment after replacement. Upgraded aftermarket arms with polyurethane bushings available but affect ride quality.

Estimated cost: $900-1,600