2003 through 2007 Dodge Cummins diesel jake brake vacuum pump from Gould Gear.
All Gould Gear pumps have a new redesigned pulley that promotes a longer pump life.
Ready to ship with pulley installed ready to install on your truck, prefilled with oil.
Sound like your vacuum pump has a rod knock? the sound is most likely a failed diaphragm which is the top of the vacuum pump. This can be easily proven by removing the pump from the truck and the four screws that attach the diaphragm to the pump base.
Squeeze the rubber hose at the bottom of the diaphragm and pull it off its connection.
A small blue silicone valve the size of a dime will be floating around inside that has come apart and that is the noise and cause of the failure. If the cam that operates the diaphragm push rod that is inside the lower base looks good and the pulley bearing feels tight you can replace the diaphragm rather than the entire pump.
Gould Gear Part Number: GG09/0307-PUMP
Part Number: GG09/0307-PUMP