The Truth About Cooling Systems

Everything the Pros Know—Finally Explained for DIYers

Engines don’t die from bad oil changes—they die from overheating. Your cooling system is the unsung hero that quietly prevents catastrophic damage every time you start your car. Yet, it’s also the most misunderstood system, surrounded by myths and bad advice that cost drivers thousands.

This guide cuts through the noise and gives you the real truth:

• How the cooling system actually works (and why each part matters).

• The truth about coolant chemistry—why it’s not about color.

• When and how often you should change coolant (and how to test it).

• The biggest myths that destroy engines—and how to avoid them.

• Simple DIY checks that save you from blown gaskets, warped heads, and huge repair bills.

• What products are worth buying, and which ones to skip.

Whether you’re a first-time DIYer or an experienced wrench, this guide arms you with the knowledge to outsmart breakdowns, save money, and keep your car on the road for years.

Because the truth is simple: a $15 jug of the right coolant can save you from a $5,000 engine replacement.