2021 GMC Savana 2500

Reliability tier: verified - see /disclosure/

Engine: 6.6L V8 Gas (L8T) (GM Gen V V8 Gas, 6.6L)

The Gen-V 6.6L L8T gas V8 in the vans (401 hp / 464 lb-ft, same rating as the HD trucks - the van did not derate it). Van intro MY2021 (replacing the L96; the vans skipped the truck's MY2020 L8T year). 6L90-E through MY2023, 8L90-E from MY2024 (the 2024 van transmission update).

Applicable failure modes (5)

• Intake-valve carbon buildup (direct injection, no port wash)
• Cooling system wear: water pump, hoses, thermostat (towing duty)
• Direct-injection high-pressure fuel pump / injector failures
• Ignition service wear: spark plugs and coils
• Valvetrain hardware failures: lifters, valves (no AFM - attribution guard)

Applicable parts (13)

• gm-hd-gas-l8t: oil-catch-can-kit (honest catalog gap)
• gm-hd-gas-l8t: coolant (service item)
• gm-hd-gas-l8t: cylinder-head (honest catalog gap)
• gm-hd-gas-l8t: fuel-filter (honest catalog gap)
• gm-hd-gas-l8t: hpfp (honest catalog gap)
• gm-hd-gas-l8t: ignition-coil (honest catalog gap)
• gm-hd-gas-l8t: injector (honest catalog gap)
• gm-hd-gas-l8t: intake-valve-cleaning-service (service item)
• gm-hd-gas-l8t: engine-long-block (honest catalog gap)
• 6.6L L8T Spark Plug (OEM)
• 6.6L L8T Spark Plug Wire (OEM)
• 6.6L L8T Thermostat Kit (OEM)
• 6.6L L8T Water Pump (OEM)

Platform recipes (3)

• Cooling inspection and wear-item service for the 6.6L L8T on a towing HD truck: pressure-test, weep hole, hoses, thermostat (mode fm-l8t-cooling-wear)
• L8T ignition service (mode fm-l8t-ignition): no L8T-specific defect exists - this is conventional Gen V truck hardware on service intervals, and the honest recipe is interval discipline
• Rough idle or hesitation on a high-mileage 6.6L L8T: direct injection leaves the intake valves unwashed - borescope before cleaning, and rule out ignition and injectors (same symptoms) (mode fm-l8t-carbon)

Recalls that include this truck (1)

• 21V-189 (March 18, 2021) - ELECTRICAL SYSTEM:12V/24V/48V BATTERY:CABLES: General Motors, LLC (GM) is recalling certain 2021 Chevrolet Express and GMC Savana vehicles equipped with 6.6L gasoline engines. The positive battery cable terminals may contact a fuse block assembly attachment post...

Matched by the model and model year NHTSA lists for each recall - a recall often covers only part of a year's production, so read its text for the build dates and versions it names. Whether a recall is still open on your VIN is not known here; check nhtsa.gov/recalls. All recalls, investigations and bulletins for this engine: /recalls/gm-hd-gas-l8t/

Reference for this truck