Ticking Noise from Engine - Broken Exhaust Manifold Bolts on 2017 Ram 1500 Hemi

ClearTheCode admin answer:

1. The Hemi Tick and Exhaust Manifold Bolts: You are absolutely correct; a ticking noise, especially on cold starts, is a very common symptom of broken exhaust manifold bolts on the 5.7L Hemi engine in Ram trucks, including your 2017 Ram 1500. The bolts, particularly on the passenger side, are prone to breaking due to thermal expansion and contraction cycles.

2. Causes:

   • Thermal Cycling: The constant heating and cooling of the exhaust manifold and cylinder head cause stress on the bolts.
   • Material Fatigue: The factory bolts can fatigue and snap over time.
   • Design: The design of the manifold and the materials used contribute to this common failure point.

3. Symptoms:

   • Ticking Noise: Most prominent on cold starts, often sounding like a faint exhaust leak.
   • Louder Under Load: The ticking may become more noticeable when accelerating or under load.
   • Exhaust Smell: You might occasionally smell exhaust fumes in the cabin.

4. Repair Process:

   • Diagnosis: A mechanic will typically inspect the exhaust manifolds for missing or broken bolts. Sometimes, the bolts break flush with the cylinder head.
   • Extraction: If bolts are broken flush, they need to be carefully drilled out and extracted. This is the most challenging part of the repair and requires specialized tools and expertise to avoid damaging the cylinder head.
   • Replacement: New, often upgraded, stainless steel bolts and new exhaust manifold gaskets are installed. Some shops may recommend aftermarket manifolds that are less prone to warping.

5. When to See a Shop:

   • Professional Help Recommended: While a very experienced DIYer might attempt this, drilling out broken bolts without damaging the cylinder head is difficult. It's generally best left to a professional mechanic or dealership, as a botched extraction can lead to much more expensive cylinder head repair or replacement.
   • Don't Delay: While not immediately catastrophic, an exhaust leak can affect engine performance, fuel economy, and potentially allow exhaust gases into the cabin. Address it sooner rather than later.