The O2 sensor on the Chrysler Town and Country should last for at least 60,000 miles without failing. When the O2 sensor does fail, it will likely generate an error code and cause the check engine light to come on. This error code can be diagnosed easily at most auto parts stores free of charge. Replacement O2 sensors can also be purchased at most auto parts stores.
Jack up on the front jack point behind the radiator.
Place jack stands underneath the front pinch welds of the vehicle and lower the Town and Country onto the stands.