This Preliminary Information communication provides information to the technician about vehicles that may have a click or tick noise heard inside cab with engine running.Technician may find the engine or High Pressure Fuel Pump tick noise that is very loud in the cab of the truck.Comparison with another truck having the same powertrain could show the other truck is quieter.Technician will install an acoustic seal that may be missing or dislodged.Update extends to all engines and all model years.