GM's Active Fuel Management (AFM) and its successor Dynamic Fuel Management (DFM) shut down half the engine's cylinders under light load to save fuel. The deactivating lifters have a long history of collapsing, dropping the rocker arm and bending pushrods. The most serious modern recall is 24V-666, covering ~597,000 trucks and SUVs with 6.2L L87 engines. This page lists every affected vehicle and explains the current remedy status.
If you own a 2021-2024 GM truck or SUV with the 6.2L L87 V8, your VIN may be covered by recall 24V-666. Free inspection, oil change to revised spec, and engine replacement if needed.
AFM lifters contain a locking pin that disengages the lifter from the cam lobe to deactivate the cylinder. Over time, the lifter can stick in the deactivated position even when full-engine operation is commanded. The result is the rocker arm dropping, the pushrod bending, and frequently camshaft lobe damage. Less commonly, the connecting rod itself fails on the L87 due to material defects in early 2021-2024 production.
| Engine | Models | Years | 2026 Status | Severity |
|---|---|---|---|---|
| 5.3L Gen IV (LC9, LMG, LH6) | Silverado/Sierra 1500, Tahoe/Yukon, Suburban | 2007-2014 | Oil consumption + AFM lifter TSBs. Class action Sloan v. GM. | High |
| 6.0L L96 (commercial) | Express, Savana, 2500/3500 HD | 2010-2019 | AFM-disabled; lifter issues rare. | Low |
| 5.3L Gen V L83 | Silverado/Sierra 1500, Tahoe/Yukon | 2014-2018 | AFM lifter failures common; many independent rebuilds. | High |
| 6.2L Gen V L86 | Silverado/Sierra 1500, Tahoe/Yukon, Escalade | 2014-2018 | AFM lifter failures; some preventive disable kits installed. | High |
| 5.3L Gen V L84 (DFM) | Silverado/Sierra 1500, Tahoe/Yukon | 2019-2024 | DFM lifter failures; no formal recall yet. | High |
| 6.2L Gen V L87 (DFM) | Silverado/Sierra 1500, Tahoe/Yukon, Escalade | 2021-2024 | NHTSA recall 24V-666 open; ~597,000 vehicles. | Critical |
| 6.2L LT1 (Camaro / Corvette) | Camaro SS, Corvette Stingray (C7) | 2014-2019 | AFM-equipped but failures less common. | Medium |
Data sourced from NHTSA recall database (nhtsa.gov/recalls). Always verify with your VIN before purchase or repair.
Recalls are tied to specific VINs, not just model years. Run yours through these free tools before you buy, sell, or schedule a repair:
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Yes, recall 24V-666 covers free inspection, oil change to revised 0W-40 spec, and engine replacement if damage is detected.
Not the federal 24V-666 recall. They are covered by separate TSBs and ongoing class action litigation.
Aftermarket tuners and disabler harnesses can void powertrain warranty. Some dealers will refuse warranty work entirely if AFM is software-disabled.
A combination of design margin (lifter pin engagement), oil-pressure variation during cylinder deactivation, and oil quality at the lifter feed gallery.
Stick to spec oil (now 0W-40 for L87), change at 5,000 miles or less in severe service, and consider an AFM-disable solution if out of warranty.
$2,500-$4,500 for a single lifter and pushrod job; $5,000-$8,000 if cam or block damage is present.