I purchased a 2010 Buick Lucerne 3 years ago with only 27,000 miles on it and now has 75,000. Love this car. So it still has the original Dex Cool and the oil shop checked it and it's good down to -32 degrees. Still nice a red in color. The owners manual says to change at 5 years or 100k whichever comes first, but the advice given to me us that since the car hasn't been driven a lot given its 14 years old, that I should just run it to 100k and then change the coolant. Do you think that's a good plan? Or would there be any benefit to changing it sooner?
I have a 2008 Buick Lacrosse CXL. Lots of Dex-Cool problems.
First the coolant was dirty, so I had the shop flush it. Then my heater core stopped working. So I ended up taking it to a Chevy dealer and asking what was wrong. The first shop had pushed some of the gunk into the heater core so the thing plugged up and had to be Blue Devil-ed (GM made this a part number because 2-3 year old cars with Dex-Cool have the same problems with the heat not working due to Dex-Cool turning into jello or cement so they tell the dealer to get you out of the warranty the cheapest way possible, and put more Dex-Cool in it, apparently!).
My heater started working again. A year later, my engine started pinging and I suspected it was carboned up from the last owner put-put-puttering around town in it not putting many miles on it. So I had the shop take the intake off and the coolant passage on the passenger side was completely full of Dex-Cool "cement" and it had damaged the upper and lower intake gaskets.
So replaced those, carbon cleaned the engine, and drilled and dissolved through the sludge/cement, and replaced the thermostat since it was all open anyway, and had them refill it with Prestone Universal All Makes, All Models.
Dex-Cool is horrible. IIRC....
1. GM got sued and it turned into a class action, which they settled, because people's cars were being ruined.
2. They claim they fixed everything. Then this happens to me and the Service Advisor at Chevy told me about the Blue Devil procedure being a GM TSB because Dex-Cool sludges up in cars that are still under warranty sometimes and the heat stops working.
3. I understand Ford switched for a few years, then ran screaming to Prestone Yellow.
4. Honda apparently used a GM engine in some things, and when GM said put Dex-Cool in it they said "LOL! NO."
You can do what you want. It's your car. But don't be surprised when you go to mess with the cooling system and you find out what's really going on in there. If it's "nothing bad", then congratulations. But most honest mechanics that aren't being paid by GM somehow admit Dex-Cool is bad news and suggest flushing it all out real good and switching to something else to avoid Dex-Crap or because they just finished cleaning out the Dex-Crap and handing you a bill.