The 2015 Silverado engine failures cluster heavily around AFM (Active Fuel Management) lifter collapse. Owners report loud ticking, sudden loss of power, and severe misfires starting as early as 8,400 miles and continuing through 152,000 miles. The lifters stick or fail without warning—one owner had it happen at highway speeds while merging, another while changing lanes; a third had both children in the truck when it lost power in a driveway. When it fails, it destroys the camshaft, bearings, and pistons. Dealers who perform partial repairs (replacing one lifter or piston) see the same misfire recur days later. Full repair per manufacturer specs—replacing VLOM, all lifters, camshaft, valves, and related parts—costs $5,600 to $17,000, and many owners end up needing complete engine replacement.
Radiators crack and leak from a faulty thermostat that over-cycles, cited in GM service bulletin PI1513F. One owner paid $1,800 to replace both. Owners also report fuel leaks from the engine at very low miles, AC compressor failure, and stalling without warning at various speeds. GM acknowledged these are known issues but denies warranty claims once mileage exceeds factory coverage, even though defects appear industry-wide. Dealers often refuse to diagnose or repair vehicles once warranty expires. One owner was left stranded in Colorado; the replacement truck GM pressured him into buying failed the same way a week later.
Failure modes owners describe
AFM/Lifter Failure with Camshaft Damage
Active Fuel Management (AFM) system lifters collapse, stick, or fail prematurely, often destroying the camshaft, bearings, and associated valve train components. This is the dominant failure mode reported across the complaint cluster. Owners describe it as a chronic issue with these engines. Repairs often require full engine replacement since incomplete repairs (single lifter or piston replacement without full component replacement per manufacturer specifications) result in recurrence.
When: Mileage ranges 8,400 to 152,000 miles; many failures occur well within expected engine life at relatively low miles (9,700–56,000 miles reported in early failures). Some failures happen during routine driving, others during acceleration or highway merging.
Symptoms owners cite: Loud ticking, clicking, or tapping noise from engine compartment; Engine misfire, pronounced misfire with loss of power; Check engine light flashing or illuminated; Severe shaking, shimmying, or jerking during acceleration; Sudden loss of motive power or hesitation; Internal engine noise (loud, grinding); Uneven acceleration; Engine stalling without warning; Limp mode activation
Codes mentioned: P0300 (Random Misfire), P050D, Cylinder-specific misfires (e.g., cylinder #6), Knock sensor faults
Repairs/costs cited: Lifter replacement alone fails; requires replacement of VLOM (Valve Lifter Oil Manifold), camshaft, all lifters, pistons, valves, and associated valve train components per ACDelco specifications. Many repairs cost $5,600–$17,000. Some dealers initially replace only one lifter or related parts, then misfires recur, necessitating further work. Engine replacement (remanufactured unit) costs $14,660 or more. One owner reports dealer covered approximately $535 under a warranty citation with owner paying ~$1,000 total; another had goodwill denied. Dealers often refuse diagnostic or repair work on out-of-warranty vehicles.
Recalls/TSBs owners mention: GM has acknowledged this is a known defect; one dealer stated 'there are known issues with these diesel trucks' and that the owner is 'not the first customer.' Service bulletins reference AFM issues. TSB PIP5498K mentioned. One owner reports GM case was opened but remained unresolved for 5+ days. Class action lawsuit alleged. GM extended warranty to 100,000 miles for 2014 models only (not 2015). Goodwill/warranty coverage often denied, especially out of warranty. One owner received offer to assist with parts after failure recurred.
Radiator Failure / Thermostat Over-Cycling
Radiator develops cracks and leaks, typically attributed to a faulty thermostat that causes excessive thermocycling (rapid heating and cooling). Service bulletin PI1513F addresses this condition, noting that excessive thermostat cycling causes tube fatigue, cracks, and leaks at radiator headers.
When: Failures reported at 40,000–102,563 miles. One failure occurred during highway driving with AC activated; others discovered while vehicle stationary.
Symptoms owners cite: Engine temperature warning / coolant low message; Coolant leak from radiator; No warning lights (in some cases)
Repairs/costs cited: Radiator and thermostat replacement quoted at $1,800 by dealers. Dealers initially refused to acknowledge TSB or perform work if VIN not on list. Some dealers did not examine the vehicle despite TSB reference.
Recalls/TSBs owners mention: Service bulletin PI1513F exists. GM extended warranty to 100,000 miles for 2014 models but not 2015 models, despite same issue present. One dealer pointed this out as unjust coverage gap.
Engine Stalling / Loss of Electrical Power
Vehicle stalls abruptly without warning at various speeds (5 MPH to highway speeds), sometimes with loss of electrical power. Some instances are recurring. One case involved recurring stalls with transmission shifting erratically.
When: Mileage range 42,000–unknown. One case recurred multiple times over several driving attempts.
Symptoms owners cite: Engine stalls without warning; Loss of electrical power; Loss of motive power / propulsion; Transmission shifting in and out of gears; Severe bucking; High engine revving; No warning lights (in some cases); check engine light in others; Vehicle can be restarted after stalling (in some cases)
Repairs/costs cited: One case resolved with ECM update (did not prevent recurrence). Other cases not repaired or issue not identified by independent mechanic.
Recalls/TSBs owners mention: Manufacturer notified in some cases, referred owner to dealer or NHTSA Hotline. No recalls identified for VINs in question.
Fuel Injector Failure / Engine Running Rich
Single fuel injector replacement performed on #6 cylinder; however, best practice suggests replacing all injectors simultaneously. Low pressure in cylinder heads and gas mixture in oil noted. One case describes engine block running rich.
When: Initial symptom (gas smell) at 86,000 miles; catastrophic misfire and failure at 108,000 miles.
Symptoms owners cite: Gasoline smell from vehicle; Misfire in #6 cylinder; Loss of compression; Check engine light; Catastrophic engine failure; Low pressure in cylinder heads; Gas mixture in oil (not brought to owner's attention during routine service)
Repairs/costs cited: Initial replacement of one fuel injector cost not stated. Full engine swap required after failure; owner paid for replacement. Borescope inspection revealed massive wash and scoring in #6 cylinder. Goodwill from GM denied.
Recalls/TSBs owners mention: Goodwill denied for engine swap.
Exhaust Manifold Bolts Breakage
Exhaust manifold bolts break off inside the engine block, causing loud knocking and squealing noise and requiring expensive engine repair.
When: Unknown mileage.
Symptoms owners cite: Strange knock sound from engine; Squealing noise on engine
Repairs/costs cited: Repair quoted at $4,000. Extended warranty does not cover.
Recalls/TSBs owners mention: No manufacturer response documented; owner believes this is a manufacturing issue.
Radiator Fracture (misc. thermal stress)
Radiator develops cracks independent of thermostat over-cycling, indicating thermal stress or manufacturing defects in radiator construction.
When: Mileage range 55,200–102,563 miles.
Symptoms owners cite: Coolant leak / radiator fluid leaking onto ground; No warning indicators (in some cases)
Repairs/costs cited: Independent mechanic pressure tested and confirmed fracture at top left corner. Repair not completed in all cases.
Recalls/TSBs owners mention: Manufacturer stated VIN not included in recall.
AC System Failure / Condenser / Compressor Issues
Air conditioning system fails, including cracked hoses, failed compressor, and blown condenser. In one case, premature belt fracture led to AC compressor failure. Another case involved condenser failure and fractured radiator discovered during routine service.
When: Failures reported at 40,000–74,298 miles.
Symptoms owners cite: AC not functioning / cooling properly; Cracked AC hose with oil leakage; Low coolant in AC system; Belt fracture generating heat; Condenser failure; No warning lights (in some cases)
Repairs/costs cited: Parts ordered for repair (hose/compressor); estimate not provided in detail. One case involved condenser and radiator fracture repair.
Recalls/TSBs owners mention: Not documented.
Fuel Leak from Engine
Fuel leaks from the engine area at very low mileage (under 10,000 miles), creating a safety hazard and strong gasoline smell in cabin. Dealership initially refused to provide pickup service.
When: 9,595 miles; vehicle 6 months old.
Symptoms owners cite: Fuel leaking from engine area; Strong gasoline smell in cabin; Safety hazard
Repairs/costs cited: No repair information provided.
Recalls/TSBs owners mention: Dealership initially uncooperative, advised owner to call fire department.
Engine Noise (Ticking) Without Identified Failure
Persistent ticking noise from engine that owner suspects is a lifter issue, but dealer claims it is normal fuel pump noise. No engine failure has occurred yet, but owner questions design adequacy.
When: Timing not specified.
Symptoms owners cite: Ticking noise like lifter out of adjustment
Repairs/costs cited: No repair performed.
Recalls/TSBs owners mention: Dealer claims noise is normal.
Ignition Switch Stuck / Starting Issues
Ignition becomes stuck in start position, rendering vehicle inoperable.
When: 81,000 miles.
Symptoms owners cite: Ignition stuck in start position; Vehicle inoperable; No warning light illuminated
Repairs/costs cited: Not diagnosed or repaired.
Recalls/TSBs owners mention: Manufacturer determined VIN not included in recall.
Engine Hesitation / Lurching / Sluggish Performance
Engine hesitates during acceleration, vehicle lurches forward erratically when braking or accelerating, or runs sluggishly and jerks abnormally. Some cases involve check engine light; others do not.
When: Mileage range 32,000–180,000 miles.
Symptoms owners cite: Vehicle hesitates or fails to accelerate when stopped; Vehicle lurches forward when accelerating or braking; Engine runs sluggishly; Abnormal jerking; Check engine light (in some cases)
Repairs/costs cited: One case: all fuel injectors needed replacement (not yet repaired). Another case: dealer replaced intake throttle box and plenum gasket (failure persisted). One case suspected engine failure requiring replacement; not yet repaired.
Recalls/TSBs owners mention: Not documented.
Catalytic Converter Failure
Catalytic converter requires replacement at relatively low mileage.
When: 91,000 miles.
Symptoms owners cite: Abnormal sound from vehicle upon starting
Repairs/costs cited: Not repaired.
Recalls/TSBs owners mention: Not contacted.
Engine Seizure
Engine seizes and requires replacement. Occurs with check engine light and 'Low Oil' message displayed.
When: 55,000 miles.
Symptoms owners cite: Check engine warning light illuminated; Low oil message displayed; Abnormally loud sounds during jumpstart attempt; Engine seized
Repairs/costs cited: Engine replacement needed; parts not available from dealer at time of complaint.
Recalls/TSBs owners mention: Not documented.
Synthesized from 88 NHTSA owner complaints — unverified consumer
allegations, summarized for patterns. The verbatim filings appear below.