BUY WITH CARE

The defining Dodge/Ram Hemi 5.7 failure is MDS lifter and camshaft wear -- the internal "Hemi tick": the multi-displacement-system (cylinder-deactivation) lifters on the deactivating cylinders wear and collapse and score the camshaft lobes. Owners report a top-end ticking, a cylinder misfire (P0300/P030x codes), rough running or shaking, metal in the oil, and in the worst cases stalling or a seized engine. 292 federal ENGINE complaints across the 2009-2019 Ram 1500, Durango, Grand Cherokee, Charger and 300 name lifters, camshaft, MDS or cylinder deactivation; among the mileage-known reports the failures cluster around 100,000 miles (median). These models are engine-mixed, so this describes the 5.7 Hemi specifically, not the 3.6 V6.

Check — Cold-start and listen for a persistent top-end tick that does NOT fade once warm (this is the catastrophic one -- distinct from the exhaust-manifold-bolt tick in HEMI-2); scan for stored or pending cylinder-misfire codes, and ask whether the camshaft or lifters were ever replaced and whether there is metal in the oil. A proper repair is a camshaft plus a full lifter set (sometimes a short block), so budget for a major engine repair on a high-mileage 5.7.

A second, later Pentastar 3.6 failure mode is valvetrain wear: a rocker-arm roller wears, loosens and drops, throwing the rocker off the cam and producing a ticking or tapping that can escalate to a misfire or internal damage if driven on. 161 federal ENGINE complaints on the 2014-2019 3.6 models (Wrangler, Grand Cherokee, the vans, Charger and 300) name rocker arms or lifters. Owners report dealer rocker/lifter replacements and PCM reflashes, with the noise often appearing at highway mileage rather than when new.

Check — Listen for a persistent tick or tap that does not clear after an oil change and is not just cold-start injector noise; ask about any rocker-arm, lifter or valvetrain work and any PCM/ECM reflash. A tick left unaddressed can score the camshaft and turn a rocker job into an engine job.