That performance comes with some well-documented issues, though. Lemon Law Help reports that Hemi owners have filed a class-action lawsuit claiming the 392 cubic inch V8 has a design flaw in its MDS, or multi-displacement system. This mechanism responds to demand on the engine by switching between four-cylinder and eight-cylinder operation. The defect causes an audible ticking noise that can be heard when starting the engine, and pieces of metal from damaged valves can circulate through the engine, damaging engine internals, cylinder walls, and camshafts.
The suit claims that Chrysler failed to honor vehicle warranties by not replacing faulty lifters or damaged engine components. Replacing a 392 hemi engine can cost a vehicle owner about $15,000 out of pocket, and replacement engines often exhibit the same issue. Fiat Chrysler issued a STAR report — a technical service bulletin to its dealership service departments – in January 2021 reporting that “Customer complaints may include abnormal engine noise, rough idle, lack of power, [and] misfire.” Technicians were instructed to check cam lobes for damage and remove the variable valve timing system’s oil control valve to check for metal debris. If debris was found, the engine should be replaced.
