Persistent Hemi Tick on my 2018 Ram 1500 5.7L

ClearTheCode admin answer:

The 'Hemi tick' is indeed a well-known concern for many 5.7L Hemi owners, and it can stem from several different issues, ranging from minor to more serious. Here's what you should consider:

1. Exhaust Manifold Leaks: This is often the most common and least severe cause. The exhaust manifold bolts can break or loosen over time, especially on the passenger side, creating an exhaust leak that sounds very much like a metallic tick. This is usually more pronounced when cold and can sometimes diminish as the engine warms and parts expand.
2. Collapsed Lifters or Worn Camshaft: This is the more serious potential cause. The hydraulic roller lifters can fail, leading to excessive play and wear on the camshaft lobe. This typically results in a louder, more consistent tick that doesn't go away. If a lifter completely collapses, it can lead to misfires and potentially trigger a Check Engine Light with codes like P030x (where x is the cylinder number).
3. Oil Viscosity/Level: While you mentioned using recommended oil, ensure the oil level is consistently full and consider using a high-quality synthetic oil if you aren't already. Sometimes, a slightly thicker oil (within manufacturer specs) can help quiet minor valvetrain noise.

When to See a Shop:

• If the tick is getting progressively louder or more consistent.
• If you notice any loss of engine power, rough idle, or misfires.
• If the Check Engine Light illuminates, especially with P030x codes.
• If you can visually confirm exhaust manifold leaks (soot around the manifold gasket).

It's advisable to have a qualified technician diagnose the exact source of the noise. They can use a stethoscope to pinpoint the area and perform further diagnostics to determine if it's an exhaust leak or a more internal engine issue requiring lifter/camshaft replacement.