A fluid exchanger may exchange a fluid (e.g., coolant) in a reservoir (e.g., vehicle radiator) by removing or withdrawing a first fluid (e.g., old, spent, used, etc.) and by introducing a second fluid (e.g., new, clean, etc.). For example, the fluid exchanger may use a negative pressure, suction, or vacuum to draw the first fluid from the reservoir, and subsequently, the second fluid may be transferred into the reservoir using a negative pressure held in the reservoir, a positive pressure applied to the second fluid, or a combination thereof. The fluid exchanger may also include a multi-purpose, hand-held nozzle that can change an operation of the fluid exchanger from a withdrawing mode to a dispensing mode.