2005 CHEVROLET SILVERADO 2500HD

Typical onset: 100,000-200,000 mi

Symptoms: hard starting when cold, white smoke at idle, rough idle, loss of power, fuel in crankcase oil (dilution), excessive blow-by

Fix: Requires cab removal (8-12 hours labor) to access injectors under the valve covers. All eight injectors typically replaced as a set due to high labor cost. Updated injectors are required to prevent repeat failure.

Estimated cost: $4,500-7,000

Typical onset: 120,000-180,000 mi

Symptoms: external coolant leaks at head gasket area, overheating, white smoke, hard starting, rough idle, reduced power

Fix: LLY injectors fail similarly to LB7 but less frequently. Head gaskets fail due to overheating from poor cooling system maintenance or towing abuse. Head gasket job is 14-18 hours, injectors another 10-12 hours if cab already off.

Estimated cost: $3,500-6,500

Typical onset: 150,000-250,000 mi

Symptoms: burning one quart every 500-1,000 miles, blue smoke on acceleration, fouled spark plugs, carbon buildup in combustion chambers

Fix: Piston ring wear and cylinder glazing are the usual culprits. Requires complete engine rebuild or short block replacement (20-28 hours). Some shops hone cylinders and replace rings only if cylinder wear is minimal (12-16 hours), but results vary.

Estimated cost: $3,500-6,000

Typical onset: 80,000-150,000 mi

Symptoms: transmission fluid leaking from radiator area, pink or milky transmission fluid, slipping gears, harsh shifts, transmission overheating

Fix: The factory transmission cooler inside the radiator fails, allowing coolant and ATF to mix. Requires immediate radiator replacement, external cooler installation, transmission flush (sometimes full rebuild if contamination is severe). Expect 4-6 hours for cooler and lines, add 12-20 hours if transmission needs rebuild.

Estimated cost: $800-1,200 (cooler only), $3,500-5,500 (with transmission rebuild)

Typical onset: 60,000-120,000 mi

Symptoms: misfire codes on multiple cylinders, rough idle, loss of power, poor fuel economy, check engine light

Fix: Individual coil packs fail due to heat and age. Diagnose which cylinders are misfiring, replace failed coils and inspect plug wires. Typically 2-3 hours labor for diagnosis and coil replacement.

Estimated cost: $400-800

Typical onset: 80,000-140,000 mi

Symptoms: service 4WD message, unable to shift into 4WD, grinding noise when engaging 4WD, 4WD indicator flashing

Fix: The encoder motor on the transfer case fails, preventing 4WD engagement. Replacement takes 2-3 hours and requires dropping the transfer case skid plate. Sometimes the entire selector switch on the dash also needs replacement.

Estimated cost: $500-900

Typical onset: 70,000-130,000 mi

Symptoms: service 4WD message, 4WD engages but no front wheel power, clicking noise from front axle, 4WD light flashing

Fix: The thermal actuator that engages the front axle fails, leaving you in 2WD even when 4WD is selected. Replace actuator and verify vacuum lines are intact. 1.5-2.5 hours labor.

Estimated cost: $300-600

Typical onset: Any mileage, especially in cold climates

Symptoms: fuel leaking from filter housing, hard starting, loss of prime, air in fuel system, check engine light with low fuel pressure codes

Fix: The plastic fuel filter housing cracks due to thermal cycling and vibration. Replace with updated metal housing and prime the system. 1.5-2 hours labor.

Estimated cost: $400-700