Need help upgrading your Fox Body Mustang's cooling system? We have all the knowledge & parts you need! The cooling system on your Fox Body Mustang is extremely critical to maintaining its performance and longevity. With the Fox Body being 20+ years old, the factory components (if they are still in place) have seen their best days and should be replaced. We get a lot of questions about what cooling modifications are needed and when. Hopefully I will help get rid of some of the cooling system myths and legends within this article!