The 2013 Lincoln MKS shares Ford's D3 platform with the Taurus and Flex. The 3.5L EcoBoost models are particularly prone to catastrophic engine failures from coolant intrusion, while both engine options suffer from transmission oil cooler and PTU leaks that can destroy the 6F transmission if ignored.
Transmission Oil Cooler Internal Leak (Coolant-into-Trans)
Common · high severityTypical onset: 60,000-120,000 mi
Symptoms: Milky pink fluid on dipstick (strawberry milkshake appearance), Harsh shifting or slipping between gears, Engine overheating due to coolant loss, Transmission failure if driven after contamination begins
Fix: Replace transmission oil cooler, flush transmission and cooling system, replace fluid and filter. If caught early: 4-5 hours labor. If trans is damaged: add 12-18 hours for transmission rebuild or replacement. This is a design flaw where the internal cooler separator fails.
Estimated cost: $800-1,200 if caught early, $3,500-5,500 with transmission damage
3.5L EcoBoost Water Pump Failure Leading to Engine Destruction
Occasional · high severityTypical onset: 80,000-130,000 mi
Symptoms: Coolant weeping from timing cover area, Overheating without obvious external leaks, Metallic knocking or rod bearing noise after overheat event, Complete engine seizure in worst cases
Fix: Water pump is internal, driven by timing chain. Requires front engine disassembly: 8-10 hours labor for pump alone. If overheating caused bearing damage (very common), you're looking at complete engine rebuild or replacement: 18-25 hours labor plus $8,000-12,000 in parts. Ford revised the pump design but damage is often already done.
Estimated cost: $1,800-2,500 for pump only, $10,000-15,000 for engine rebuild/replacement
Power Transfer Unit (PTU) Seal Leaks and Fluid Starvation
Common · medium severityTypical onset: 70,000-110,000 mi
Symptoms: Fluid puddles under front-center of vehicle, Whining or growling noise during acceleration, Shuddering when turning in AWD models, Complete PTU failure with grinding/clunking
Fix: PTU seals fail and there's no dipstick or service interval from Ford, so owners don't catch it until damage occurs. Seal replacement: 3-4 hours. PTU replacement if seized: 5-6 hours plus $1,200-1,800 parts. Check fluid every oil change—it takes 75W-140 gear oil.
Estimated cost: $400-700 for seals, $1,800-2,800 for PTU replacement
Carbon Buildup on Intake Valves (EcoBoost Direct Injection)
Common · medium severityTypical onset: 60,000-100,000 mi
Symptoms: Rough idle and misfires at cold start, Loss of power and reduced fuel economy, Check engine light with multiple misfire codes (P0300-P0306), Hesitation during acceleration
Fix: Direct injection means no fuel washing over intake valves. Carbon cakes up and chokes airflow. Walnut blasting required: remove intake manifold, blast each port: 4-6 hours labor. Some shops use chemical cleaning but results are temporary. This will recur every 60-80k miles.
Estimated cost: $500-900
Steering Electric Power Assist Sensor Failure
Occasional · medium severityTypical onset: 90,000-140,000 mi
Symptoms: Steering assist cuts out intermittently (sudden heavy steering), Warning message 'Power Steering Assist Fault', More common in cold weather initially, then becomes permanent, No loss of steering control, just loss of assist
Fix: Torque sensor in the steering column or EPAS module failure. Diagnosis: 1 hour. Sensor replacement: 2-3 hours (column disassembly). Module replacement: 1.5 hours plus programming. Ford issued TSB 13-8-9 but no recall despite NHTSA investigation.
Estimated cost: $800-1,400
Fuel Pump Driver Module Failure
Occasional · high severitySymptoms: No-start condition with good battery and starter, Engine stalling while driving at any speed, Intermittent no-fuel condition that eventually becomes permanent, No fuel pump priming sound when key is turned on
Fix: Module is mounted to the frame rail behind fuel tank. Corrodes and fails, especially in rust belt. Not the pump itself—the electronic driver module. Replace module: 1.5-2 hours. Ford recalled some batches but not all years comprehensively. Easy diagnosis with fuel pressure gauge.
Estimated cost: $350-600
Transmission Mounting Bracket Failure
Occasional · medium severityTypical onset: 80,000-130,000 mi
Symptoms: Clunking when shifting from Park to Drive or Reverse, Excessive drivetrain movement felt through chassis, Vibration at idle in gear, Visible cracking in mount or bracket
Fix: The 6F50/55 transmission mount and subframe bracket crack from the weight and torque of the EcoBoost. Mount replacement: 2-3 hours. If bracket is cracked, subframe must be dropped: add 4-5 hours. Inspect mounts during every service—catching early prevents subframe damage.
Estimated cost: $400-700 for mount, $1,200-1,800 if subframe bracket involved
Avoid the 3.5L EcoBoost unless you have full service records proving preventive maintenance—engine and transmission failures are financially catastrophic. The 3.7L V6 is more reliable but still suffers transmission cooler and PTU issues that require vigilant monitoring. Buy only with extended warranty or significant cash reserve for repairs.
AI-assisted summary drawn from NHTSA recall data, our labor-times database, and platform knowledge. Not a substitute for a pre-purchase inspection on a specific vehicle.