Reader Question I have a 2000 GM 1500 pickup with the 4800 v8. Recently, my wife was told by the dealer that we had the wrong coolant in the engine and it needed a “radiator flush” and the proper orange coolant put in. Or else it would damage the engine, etc.
I checked the manual and it did say use only Dex-Cool in it. Ok, but this sounds like a matter of draining the radiator and putting the Dex Cool in. It seems like they were trying to scare my wife into an expensive “radiator flush” to me.
Am I correct in draining and replacing the coolant?
Yes, you can drain and refill the radiator with the proper Orange coolant. There will still be some green coolant residue left over inside the engine, and the two coolants do not mix well together, so try to remove as much of the green stuff as possible.
You can remove the lower radiator hose and stick a garden hose in the radiator neck to flush as much of the radiator as possible.
With the lower hose removed you can also start the engine for a few seconds to allow the water pump to push out the remaining coolant from the engine. This can be a little messy.
Also do this with the engine temperature COLD so you do not burn yourself. Your local fast lube place probably has a coolant flushing machine that will do a great job at removing all the green coolant. You might want to call around and get a price if you don’t want to do it yourself.