What is the thumping noise in my truck after having the water pump replaced?
Only when the heater is on, doesn't matter which mode A/C, defrost or vent.
The thumping is fairly consistent at about 1 second intervals and varies
in volume from soft to heard from across the street. After the vehicle is
turned off, the noise continues for another
minute or so and can be heard very well under the hood but not easily pin
pointed. You can feel the thump on basically every cooling system
component, radiator, hoses, water pump.