2022 GMC SIERRA 3500HD

Typical onset: 40,000-80,000 mi

Symptoms: Metallic knocking from bottom end especially on cold start, Oil consumption increase, Low oil pressure warning, Metal shavings in oil filter, Sudden catastrophic failure with rod through block

Fix: Complete engine rebuild or short block replacement required. 30-45 labor hours depending on cab-off or cab-on approach. Includes pistons, rings, bearings, machining, sometimes crankshaft if journals are scored. Root cause traced to insufficient piston-to-wall clearance and weak wrist pin bushings on early 2020-2022 builds.

Estimated cost: $18,000-28,000

Typical onset: 60,000-100,000 mi

Symptoms: Transmission fluid leak visible near radiator, Pink/red fluid dripping from front of truck, Transmission overheating, Low trans fluid warnings, Reduced towing capacity due to overheat

Fix: Replace cooler lines and often the cooler itself. Lines rust or crack at crimps. 3-5 labor hours. If coolant contaminated trans fluid, flush and filter change mandatory, sometimes full trans rebuild if caught late.

Estimated cost: $800-1,500

Symptoms: 'Service Exhaust Fluid System' message, DEF gauge reads empty when tank is full, Reduced engine power mode, Won't start after sitting in cold weather, Range countdown to 'speed limited to 55 mph'

Fix: DEF tank heater element or level sensor fails, or crystallized urea clogs injector. Tank drop and clean, heater/sensor replacement, sometimes injector. 4-7 labor hours. Cold climates see this accelerate. Use quality DEF and keep tank above 1/4 full.

Estimated cost: $1,200-2,800

Typical onset: 80,000-140,000 mi

Symptoms: White smoke from exhaust, Coolant loss with no visible external leak, Milky oil or coolant in overflow tank, Overheating, Rough idle and misfire codes

Fix: Both head gaskets typically replaced at once. Cab-off procedure recommended for access. 25-35 labor hours. Heads resurfaced, ARP studs recommended over TTY bolts for boosted applications. Check for cracked heads while apart.

Estimated cost: $6,500-9,500

Typical onset: 70,000-110,000 mi

Symptoms: Clunk on acceleration or deceleration, Excessive driveline vibration, Visible sag or tearing in rubber mount, Drivetrain noise during gear changes

Fix: Replace transmission crossmember mount. Common on trucks used for heavy towing or off-road. 1.5-2.5 labor hours. Inspect transfer case mount at same time if 4WD.

Estimated cost: $350-650

Typical onset: 50,000-90,000 mi

Symptoms: Hard starting especially after sitting overnight, Extended cranking, White smoke on startup, Fuel smell under hood, Loss of prime requiring multiple key cycles

Fix: Filter housing seals shrink and crack. Replace filter head assembly or reseal with updated O-rings and hand primer. 2-3 labor hours. Also check fuel line quick-connects for cracks. Keep fuel filter changes at 15k intervals max.

Estimated cost: $600-1,200