My 2011 Ram 1500 5.7 L makes a loud squeaking noise after about 10-15 minutes of driving. The noise does not increase or decrease with engine RPM. The sound gets louder under the passenger side behind the engine.
I took it to the dealer. They replaced idler pulley, but it never went away.
What could be causing this? How do I diagnose this?
If the noise is independent of engine rpm or vehicle speed it is not directly connected to the engine, the transmission nor drive train.
I suppose some electrical/hydraulic driven pump/actuator, since that would be the only thing that maintains the same rpm/frequency independent of engine or vehicle speed. Due to the lack of alternatives i think this could be either the fuel pump or the power steering control.
Can you further describe the noise? When the noise appears, does it persist when you stop and restart the engine?
