Expanded Tube or Mechanical Heater Cores

Expanded tube heater cores, also known as mechanical heater cores, first hit the market in the 1990s for Chrysler and high-end import applications. This style consists of copper tubes, aluminum fins, and plastic tanks. There are some models that do not have a bottom tank, therefore the tubes are exposed. Aftermarket models with this style have been designed with aluminum tubes and OE applications have started following suit.