Late-model Hemis have plagued owners with a notorious ticking sound for over 15 years, and Dave Miller, a mechanic who has rebuilt more than 2,000 of these engines, says he has identified the root cause.
The tick affects 5.7-liter and 6.4-liter Hemi V8s built from 2009 onward in Ram, Jeep, Dodge, and Chrysler vehicles. The problem traces to valvetrain lifters that fail to receive adequate oil. When lifter rollers lack lubrication, their internal needle bearings disintegrate. Once they stop rolling, the cam lobe grinds against them, producing the tick. This eventually causes a misfire and risks a total engine rebuild if left unaddressed.
Miller used a borescope to compare oil galleries in early Hemis against 2009-and-later models. Early versions feature a small hole that allows oil to flow into the lifter as it rises and falls. The 2009-and-up Hemis lack this hole entirely. Miller attributes the omission to a cylinder block design change that accommodates a longer camshaft snout required for variable valve timing on newer engines, while cam journal designs remain largely identical.
Miller is developing a modified lifter design to address the issue. He has established a GoFundMe seeking $5,000 to complete the project, and had raised $4,369 at the time of reporting. A pinned YouTube comment from an alleged 30-year Chrysler service department veteran endorsed Miller's findings.