The 2015 F-250 represents the second year of Ford's fourth-gen Super Duty. The 6.2L gas V8 is bulletproof, but the 6.7L Power Stroke diesel has well-documented catastrophic failure modes that can grenade engines between 60,000-150,000 miles if not caught early.
6.7L Power Stroke Catastrophic Engine Failure (Piston/Bearing/Crankshaft)
Occasional · high severityTypical onset: 60,000-150,000 mi
Symptoms: Sudden loss of power under load, Metallic knocking or rattling from crankcase, White or blue smoke from exhaust, Metal shavings in oil, Low oil pressure warning, Engine seizure in extreme cases
Fix: Complete engine rebuild or replacement required. 30-50 hours labor for in-chassis rebuild with new pistons, rings, bearings, and crankshaft machining. Many shops recommend long-block replacement instead. Root cause often traced to oil dilution from regen cycles or failed CP4 injection pump sending metal through the system.
Estimated cost: $15,000-25,000
CP4.2 High-Pressure Fuel Pump Failure (6.7L Diesel)
Occasional · high severityTypical onset: 80,000-120,000 mi
Symptoms: Hard starting or no-start condition, Loss of power, rough running, Metal contamination throughout fuel system, Fuel in oil (dilution), Check engine light with fuel pressure codes
Fix: When the CP4 fails, it sends metal debris through entire fuel system. Requires new pump, all eight injectors, fuel lines flushed or replaced, tank cleaned, lift pump. 12-18 hours labor. Many owners install CP3 conversion kit ($3,500-5,000) as permanent fix to prevent recurrence.
Estimated cost: $8,000-12,000
Transmission Oil Cooler Line Failure
Common · medium severityTypical onset: 70,000-110,000 mi
Symptoms: Transmission fluid leaking near radiator, Overfilled coolant reservoir with milky appearance, Transmission slipping or harsh shifts, Overheating transmission, Coolant in transmission pan (catastrophic if not caught)
Fix: Ford 6R140 transmission cooler lines corrode internally, allowing coolant and ATF to mix. Requires new cooler lines, external cooler recommended, complete fluid flush of both systems. 4-6 hours labor. If coolant entered transmission, full rebuild needed (add $3,500-5,000).
Estimated cost: $800-1,500
EGR Cooler Failure (6.7L Diesel)
Common · medium severityTypical onset: 90,000-130,000 mi
Symptoms: White steam from exhaust, Coolant loss with no external leaks, Rough idle when cold, Check engine light with EGR codes, Sweet smell from exhaust, Overheating
Fix: EGR cooler cracks internally, dumping coolant into exhaust stream. Ford redesigned this part twice. Requires new cooler, often caught during head gasket diagnosis. 6-8 hours labor. Must delete EGR valve and clean intake during repair.
Estimated cost: $1,800-2,800
Turbocharger Variable Geometry Actuator Sticking
Common · low severityTypical onset: 60,000-100,000 mi
Symptoms: Check engine light with turbo underboost codes (P0046, P003A), Sluggish acceleration, Black smoke under throttle, Limp mode activation, Turbo whistle or squealing
Fix: Variable vane mechanism in turbo sticks due to carbon buildup or actuator failure. Often cleaned and freed up first (2 hours labor), but may require turbo replacement or rebuild if vanes are damaged. Catch it early to avoid full turbo replacement.
Estimated cost: $400-2,500
Cab Corner and Rocker Panel Rust (All Models)
Common · low severitySymptoms: Visible rust bubbling behind rear wheels, Rust perforation at cab corners, Rocker panels rusting from inside out, Common in salt-belt states after 5-7 years
Fix: Ford's aluminum body doesn't prevent steel cab and bed corrosion. Requires cutting out rust, welding in new metal, and refinishing. 8-12 hours body shop labor. Preventive undercoating helps but doesn't reverse existing rust. Structural concern if left unchecked.
Estimated cost: $1,500-3,500
Front Wheel Bearing Failure
Occasional · medium severityTypical onset: 80,000-120,000 mi
Symptoms: Growling or rumbling noise that increases with speed, Noise changes when turning, Wheel play when jacked up, ABS light may illuminate, Uneven tire wear
Fix: Unit bearing assembly replacement. 2-3 hours per side labor. These trucks are heavy and if used for towing, bearings wear faster. Both sides rarely fail simultaneously but worth inspecting both when doing one.
Estimated cost: $400-700
Buy the 6.2L gas if you don't need the diesel's towing capacity—it's anvil-reliable; the 6.7L diesel is powerful and can last 300k+ miles with religious maintenance, but the catastrophic failure risk and $8k-25k repair costs make it a gamble on used examples without full service records.
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.