How to Make Your Car Last Forever: Avoid Expensive Repairs, Improve Fuel Economy, Understand Your Warranty, Save Money

Ethylene glycol antifreeze has been used for years without problems. The key is to inspect it every six months
for protection and color and replace it every two years or 25,000 miles, whichever comes first. If the
protection goes above –34° F, then I would replace it. Also, if the color gets dark, brown, or rusty, replace it
and perform a cooling system flush to remove harmful rust and scale buildup in the system.