I am driving a 1998 XJ8 4.0L V8. The water pump on the front of the engine is wobbling a tad when running the car. A ticking noise is herd as well, not sure if they are associated. Also when looking at parts, I saw a water pump, and an auxiliary water pump. Which would be needed to replace the wobbling piece? It still runs fine and doesn't have any known problems

 

The auxiliary pump is for the heater. It would be best if you don't drive the car until the pump is replaced. Failure could cause overheating before the temp. gauge can warn you.

 

Do i need to replace the auxiliary pump or just the water pump, because only the water pump on the front is moving.

 

they are independent

the auxilary pump is electric, so no externally visible moving parts.