I have a 2006 Chevy Impala that I notice is leaking DexCool coolant looks like from the rad. I have had to fill coolant only twice in the rad and overflow, but the cars temp is not overheating.
I am getting very little heat in cab at idle and “warm” with heat on full when driving. Hotter with higher speeds. I checked the oil and thankfully it’s a golden brown. Nothing in there. But there is signs of Dexcool over the fans in front of the rad, but doesn’t feel like it’s coming from a hose. Any ideas?
First thing you need to do is get a cooling system pressure test at your local mechanic or fast lube place. They will basically use an air pump and attach it to your radiator and pump air into the system to help push out the existing coolant to make the leak obvious to the naked eye.
You don’t have heat at slow speeds because there is not enough coolant circulating in the engine to produce the heat. At higher speeds the water pump is working much hard at pushing what ever amount of coolant it can through the engine and heater core inside the dash.
Fixing the leak and topping off with coolant will probably fix both issues.