How to Add Coolant: Chrysler 300 (2005-2010) - 2005 Click to view0:33Adding engine coolant (also known as antifreeze) to your 2005 Chrysler 300 is pretty easy. Engine coolant circulates through your engine to keep it cool in the summer but won't freeze in the winter. Make sure to check your engine when it is cold for an accurate reading. Engine Cooling for Chrysler 300 - AutoZone Get Your Chrysler 300 Engine Cooling from AutoZone.com. We provide the right products at the right prices.