One the 3.9L V6 and 5.9L V8 the carbon buildup on the top of the piston is common. As the buildup increases with mileage and over time, symptoms may vary from light ticking, to ticking/hammering, to hammering/knocking noises. Fuel injector cleaner often solves the problem.
Carbon buildup at top of piston may cause noise on Dodge Ram 3500
Average mileage: 176,000 (176,000–176,000)
Engine affected: 5.9L V8
10 people reported this problem
1999 Dodge Ram 3500 - 5.9L V8 176,000 mi, Visitor
just noticed when pulling the trailer, there is ticking noise mainly when motor is lugging