GM 6.2L V8
6.2L AFM/DFM cylinder deactivation diagnosis
Cylinder-deactivation faults on the 6.2L L86/L87.
Why this matters on the GM 6.2L V8
The 2014–2018 L86 uses AFM; the 2019+ L87 uses DFM. Lifter failures on deactivating cylinders are the most common major repair.
Symptoms owners notice
- Misfire on specific cylinders
- Tick at idle
- Rough running
What we check
- Misfire counters
- Oil pressure
- Valvetrain inspection
Repair work involved
- Lifter and valvetrain repair to factory configuration