Your engine fluids have their respected reservoir for secure and proper storage. In the case of your engine cooling system, your coolant fluid stays inside a coolant tank or reservoir when not in use. Because the use of coolant is governed by a number of mechanisms for flow regulation or control, it may stay inside the tank for a long time especially under extremely cold climates because your engine needs to be heated properly. Because of the heat build-up, the coolant may evaporate and condense or expand which often leads to spillage. To address such circumstance, installing Audi A4 Radiator Expansion Tank is a practical solution to prevent wasting your precious coolant. This added coolant or fluid reservoir often has high grade plastic material construction. As an extra fluid storage, it is called expansion tank to receive coolant once it fills from the tank reservoir as your engine’s climate control components are put to work to manage operating temperature. With this storage system, no coolant is lost or wasted as the level rises and fall when coolant expands and contracts. For older car expansion tank installation, all you need to do is mount the part near the radiator, connect it to the overflow tube, and seal or replace the cap. For your 1998Audi A4 Radiator Expansion Tank application, Aftermarket G1030-87907 must be considered for heavy duty and quality tank features to install. Designed and molded as a direct-fit part or stock replacement, it requires minimum fuss on fitment. As a trusted source of Aftermarket Radiator Expansion Tanks, we offer convenient online shopping serving you better in covering your Audi radiator expansion tank needs.