An expansion tank in a vehicle allows extra room for liquids and lubricants to expand out of the main reservoir as the engine heats up. Cheap replacement expansion tanks for any vehicle are available at Car Parts 4 Less.
When your vehicle is switched off and stationary, the liquids and lubricants that are used in components like the cooling and heating systems are in a low-temperature state, so they can sit stored in the main reservoir. When the engine is on and said systems are in use, however, the liquids increase in temperature and, therefore, expand, which means they need extra room. That's where the expansion tank comes in. The ultimate function of an expansion tank is to protect the whole system from excessive pressure, so a damaged tank can have long-term ramifications on the health of your air conditioning (AC) or heating systems. This could lead to expensive repairs when a cheap replacement expansion tank in the first place would do, so be sure to look out for early signs of a faulty system, such as a lack of cool air.