Twenty-one complaints describe distinct engine failures. The most severe: three separate engine fires, two destroying the vehicle entirely, one occurring right after an engine block heater core recall repair at a Ford dealer. One fire occurred at 190k miles; another at 25k; a third involved brake stiffness before the engine compartment caught fire.
High-pressure fuel pump (Bosch CP4) failure at 64k miles resulted in metal shavings throughout the engine and total engine failure. Ford is aware and sells a $6,000+ repair kit, but one owner lost all power at 70+ mph on the highway with no power steering or brakes.
NOX sensor failures appear repeatedly between 43k and 56k miles. A TSB exists for water ingress into the wiring harness connector on the right frame, causing corrosion and throwing a P2209 code. One owner faced a $1,600+ bill after exceeding the 80k-mile emission warranty by 2,000 miles, despite the known design flaw.
Intake manifold problems, abnormal knocking, engine seizure with parts falling out, violent vibration pushing the truck off the road, and recurring stall-and-no-start conditions (one recurring three times in 18 months with a melted wiring harness) round out mechanical failures. One truck stalled at 57k miles requiring complete engine replacement. Motorcraft oil filters leak around the rolled edge, risking total oil loss on the 6.7 diesel. DEF pump failure at 200 miles left one new truck in the shop two weeks waiting for parts.
Failure modes owners describe
Engine fire
Engine compartment fire, some reaching cabin and consuming entire vehicle. Fires started under hood or from rear of engine, often with smoke first appearing.
When: Between 25k and 190k miles; one fire occurred immediately after engine block heater core recall repair
Symptoms owners cite: Smoke from under hood or grille; Fire visible in engine compartment; Fire entering cabin; One case: brake pedal firm and difficult to depress before fire; One case: dark gray smoke when placing vehicle in reverse
Repairs/costs cited: Two vehicles destroyed; one unrepaired at dealership since July 2020 with manufacturer unresponsive despite dealer sending pictures
Recalls/TSBs owners mention: One case: manufacturer opened case and provided case number; cases involved recall for engine block heater core (at least one fire occurred post-recall)
NOX sensor failure
Emission system NOX sensor failure caused by water ingress into wiring harness connector mounted on right outside frame, leading to corrosion and short. TSB issued. Throws P2209 code and causes major power loss.
When: 43k to 55.9k miles
Symptoms owners cite: Check engine light illuminated; Major reduction in power while driving; Vehicle can only idle
Codes mentioned: P2209
Repairs/costs cited: One owner quoted $1,600+ for repair; one sensor replaced at dealer then failure reoccurred
Recalls/TSBs owners mention: TSB issued; dealership aware of problem; Ford has issued TSB for emission system wiring harness
High-pressure fuel pump failure
High-pressure fuel pump (Bosch CP4) failed, with metal shavings spreading throughout engine resulting in total engine failure. Owner notes Ford aware of issue and offers a kit to fix.
When: 64k miles
Symptoms owners cite: Low fuel pressure and reduced power warning lights; Vehicle stalled and failed to restart
Repairs/costs cited: Engine failure; vehicle not repaired, remained at dealer; fix kit costs over $6,000
Recalls/TSBs owners mention: Manufacturer notified; Ford aware of Bosch CP4 contaminated fuel system issue and offers repair kit
Intake manifold failure
Intake manifold defective or fractured. Two separate complaints; one involved bolts connecting EGR valve to exhaust intake fractured during EGR valve replacement.
When: 49k and 55k miles
Symptoms owners cite: Abnormal ticking sound from engine compartment; Check engine light (in EGR case)
Repairs/costs cited: Both vehicles not repaired; one required replacement bolts in addition to EGR valve replacement
Recalls/TSBs owners mention: One case: manufacturer opened case; other case: no assistance offered
Engine knock and bearing failure
Abnormal knocking sound from engine, one case during oil change. Unknown engine parts detached and fell to ground; loss of motive power. Second case diagnosed as defective intake manifold.
When: 30k and 55k miles
Symptoms owners cite: Abnormally loud knocking sound; Engine oil leaking onto ground; Unknown engine parts detached and fell; Loss of motive power
Repairs/costs cited: First case: not diagnosed or repaired by mechanic or dealer; second case: estimate provided but not repaired
Recalls/TSBs owners mention: Manufacturer made aware; case opened in first instance; warranty expired by second case
Engine stall and failure to restart
Engine stalled while parked or during operation and failed to restart. One case involved melted wiring harness (repaired once, then recurring). One involved long crank no start recurring three times in 18 months.
When: 57k miles and recurring within 18-month period
Symptoms owners cite: Vehicle stalled; Failed to restart; Check engine light; Long crank before starting (in recurring case)
Repairs/costs cited: One melted wiring harness fixed, but problem recurred; one case required multiple tows to dealership with recurring long crank issue
Recalls/TSBs owners mention: Manufacturer notified and referred to NHTSA; no repair completed in stall-only case
EGR valve failure
EGR valve faulty and required replacement. During replacement, bolts connecting EGR valve to exhaust intake fractured and also required replacement.
When: 95k miles
Symptoms owners cite: Check engine light illuminated
Repairs/costs cited: Replacement bolts needed in addition to EGR valve; vehicle not yet repaired at time of complaint
Recalls/TSBs owners mention: Manufacturer notified; no assistance offered
Violent vibration and loss of control
Vehicle vibrated violently when driving over bumps or at highway speed, pushing vehicle off road. Occurred intermittently, no warning lights.
When: 31.25k and 52k miles
Symptoms owners cite: Violent vibration while driving; Vehicle pushed off road; Intermittent occurrence
Repairs/costs cited: Vehicles not diagnosed or repaired
Recalls/TSBs owners mention: Manufacturer made aware; no assistance provided
Oil filter leakage
Motorcraft FL-2051-S oil filters leaking due to improper manufacture. Leaks occur around rolled top of filter can. Owner had two filters both leak, risking total oil loss.
When: Not specified
Symptoms owners cite: Oil leaking from filter; Risk of engine losing all oil
Repairs/costs cited: Owner has pictures of leaking filters; affects 6.7 diesel engine
DEF pump failure
DEF pump failed very early, requiring replacement. Ford did not have replacement part in stock, leaving truck in shop.
When: 200 miles
Symptoms owners cite: Check engine light illuminated
Repairs/costs cited: New truck in shop 2 weeks waiting for part availability
Coolant pipe O-ring leakage
O-rings inside coolant pipes leak in cold weather conditions. Owner suggests this warrants recall.
When: Cold weather occurrence
Symptoms owners cite: Coolant leaking from O-rings in pipes during cold weather
Synthesized from 21 NHTSA owner complaints — unverified consumer
allegations, summarized for patterns. The verbatim filings appear below.