Tom

Tom,

Q I have a 2009 Chevy Silverado 1500 with 32,000 miles on it, and I drive

it for work. My repair shop suggested I replace the engine coolant. I
consulted my maintenance schedule and cannot find a recommended drain
interval for the coolant. What’s up with that? Is it supposed to last forever?

Charles—Detroit,    Michigan

Charles,

A According to GM, Dexcool (which is what the coolant is in your vehicle)

is supposed to last to 150,000 miles or more without needing to be changed. I
checked the GM maintenance schedule for your truck and could not find a
drain interval recommendation up to and over 150,000 miles. I simply do not
subscribe to this service suggestion from GM. Too many problems have
cropped up with Dexcool, but that is another subject dealt with in the cooling
system chapter. Based on extensive experience, I recommend you flush and
fill the cooling system every two years or 24,000 miles, whichever comes
first. This way you head off problems in the form of rust, scale, and acid
buildup at the pass.