2015 CHEVROLET SILVERADO 2500HD

Typical onset: 80,000-150,000 mi

Symptoms: sudden loss of power, metal shavings in fuel system, won't start after running fine, fuel in oil

Fix: CP4 pump grenades internally, sending metal through entire fuel system. Requires pump, injectors, fuel lines, tank cleaning, sometimes new turbo. 20-30 hours labor depending on contamination extent. This is the nightmare scenario for LML owners.

Estimated cost: $8,000-15,000

Typical onset: 70,000-120,000 mi

Symptoms: reduced engine power message, DEF quality poor warning, excessive regen cycles, check engine light with P codes

Fix: DPF clogs from short trips or failed regens; DEF injector and lines crystallize. DPF replacement or cleaning 6-8 hours, DEF system overhaul 4-6 hours. Many owners delete (illegal for road use).

Estimated cost: $1,500-4,500

Typical onset: 90,000-140,000 mi

Symptoms: white smoke at startup, coolant loss with no visible leak, rough idle when cold, coolant in intake tract

Fix: EGR cooler develops internal cracks, leaking coolant into exhaust or intake. Replacement requires 8-10 hours, includes new EGR valve typically. Often done with DPF work as preventive measure.

Estimated cost: $2,000-3,200

Typical onset: 60,000-100,000 mi

Symptoms: transmission fluid puddles under truck, low fluid warnings, burnt fluid smell, slipping when hot

Fix: Steel cooler lines rust at bends and fittings, especially in salt states. Line replacement 2-3 hours, but often discover cooler itself is clogged requiring radiator R&R adding 4-6 hours total.

Estimated cost: $800-2,200

Typical onset: 80,000-120,000 mi

Symptoms: clunk when shifting into drive or reverse, vibration at idle in gear, visible torn rubber on mount

Fix: Duramax torque tears the rear transmission mount. Simple replacement, 1.5-2 hours. Do both motor mounts at same time if they're original.

Estimated cost: $350-600

Typical onset: 100,000-180,000 mi

Symptoms: rough idle, white or black smoke, fuel smell in oil, hard starting, individual cylinder misfire codes

Fix: Injectors crack internally or fail electrically. Each injector 2-3 hours labor; usually replace all 8 if one fails due to age. Requires return line and cup updates on some.

Estimated cost: $4,000-6,500

Typical onset: 70,000-110,000 mi

Symptoms: gear oil drips on driveway, 4WD won't engage, clicking from front axle, fluid on front diff housing

Fix: Actuator seals leak, sometimes the actuator motor fails. Seal replacement 2 hours, actuator 3 hours if it needs electrical diagnosis. Not a breakdown but kills 4WD.

Estimated cost: $400-900