I have a 98 dodge Ram 2500 with the 5.9. The engine runs fine when cold but as it warms up and I give it gas I hear a knock in the engine. It almost sounds like a loose rocker arm, if so are these hyd. or can I adj. them or maybe its something completely different. I was going up a steep hill the other day and it was very noticable. I cannot hear it knock until i rev it up. only has 56000 miles on it. Any suggestions?[sm=dontgetit.gif]

 

Rocker arm is usually more of a tick, but if you think it is a rocker then it may very well be a dropped valve seat issue. Do a compression test and leakdown if possible.