The 2016 Taurus is a solid full-size sedan platform-wise, but the 2.0L EcoBoost and 3.5L EcoBoost engines have earned notoriety for catastrophic low-speed pre-ignition (LSPI) issues and carbon buildup, while the 6F transmission suffers from internal cooler failures that contaminate fluid and destroy clutch packs.
Low-Speed Pre-Ignition (LSPI) Engine Failure - EcoBoost Models
Occasional · high severityTypical onset: 30,000-80,000 mi
Symptoms: Sudden catastrophic knocking under light throttle acceleration at low RPM, Metal shavings in oil, complete loss of power, Cracked pistons, bent connecting rods, scored cylinder walls, Often happens with no warning, engine grenades in seconds
Fix: Complete engine rebuild or short block replacement required. 16-24 hours labor depending on accessibility and whether turbos need removal. This is a known Ford EcoBoost defect exacerbated by direct injection and turbo boost at low speeds with high load. Use only spec oil (5W-30 meeting WSS-M2C946-A) and avoid lugging the engine.
Estimated cost: $6,500-12,000
6F55 Transmission Internal Oil Cooler Failure
Common · high severityTypical onset: 60,000-120,000 mi
Symptoms: Shuddering or slipping between gears, especially 3-4 or 5-6, Transmission fluid appears milky or contaminated (coolant intrusion), Harsh engagements, delayed shifts, Check engine light with transmission-related codes (P0868, P0730)
Fix: Internal cooler ruptures, allowing coolant into ATF and destroying clutch packs. Requires transmission removal, full rebuild or replacement, plus external cooler flush. 12-16 hours labor. Some techs add external auxiliary cooler to prevent recurrence.
Estimated cost: $3,500-5,500
Carbon Buildup on Intake Valves - EcoBoost Direct Injection
Common · medium severityTypical onset: 80,000-120,000 mi
Symptoms: Rough idle, misfires at cold start, Loss of power, poor fuel economy, Check engine light with misfire codes (P0300-P0304), Failed emissions testing
Fix: Direct injection leaves no fuel wash on intake valves, causing heavy carbon deposits. Requires walnut blasting or manual cleaning of intake valves with intake manifold removal. 6-8 hours labor for 2.0L, 8-10 hours for 3.5L due to accessibility.
Estimated cost: $800-1,400
PTU (Power Transfer Unit) Seal Leaks and Failure - AWD Models
Occasional · medium severityTypical onset: 70,000-110,000 mi
Symptoms: Fluid leak at front of transmission/PTU junction, Grinding or whining noise from front axle area, AWD malfunction light, reduced power in AWD mode, Burning smell if fluid level drops critically low
Fix: PTU shares fluid with transmission and frequently develops seal leaks or internal bearing failures from inadequate lubrication. Requires PTU removal and rebuild or replacement. 5-7 hours labor. Critical to catch early before bearings seize.
Estimated cost: $1,200-2,200
Water Pump Failure - 3.5L EcoBoost
Occasional · high severityTypical onset: 60,000-100,000 mi
Symptoms: Coolant leak from timing cover area, Overheating, high temperature gauge readings, Coolant warning light or low coolant message, Squealing noise from front of engine
Fix: Water pump is internally mounted behind timing cover. Requires timing cover removal, timing chain inspection/replacement recommended while in there. 10-14 hours labor. This is a preventive maintenance item that becomes catastrophic if ignored.
Estimated cost: $2,000-3,500
Rear Suspension Toe Link Fractures
Occasional · high severityTypical onset: 80,000-140,000 mi
Symptoms: Clunking noise from rear during bumps or turns, Severe rear-end instability, car feels loose, Abnormal tire wear on inside edges, Visible crack in rear lower control arm/toe link
Fix: Ford issued recall 16S19 for rear toe link fractures. Even post-recall vehicles can develop cracks from corrosion and stress. Requires replacement of affected links and alignment. 2-3 hours labor per side if not covered under recall extension.
Estimated cost: $400-800
Skip the EcoBoost models unless you can verify obsessive maintenance history—too many grenaded engines and transmission cooler failures make these expensive gambles; the naturally aspirated V6 versions are far more reliable but increasingly hard to find.
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.