I’ve been trying to figure this out for the past 6 months. I have a 2011 sierra 2500 with the 6.6, and I’m have this weird issue with my coolant. Low coolant light comes on and I can see that the tank is about 3/4 full, never less than that regardless of how much I drive without topping it off. When I do top it off and drive it, it can go a while (2-3 days) without the low coolant warning pop up again.
I do notice though, when I do add more to the tank and drive enough to lower the level, some coolant is added to the overflow tank. Not a huge issue, seems it doing it’s job as the coolant expands due to the heat, but eventually the overflow will fill all the way up and start leaking out the drain hole. I’m not sure if the overflow is supposed to eventually empty back into the reservoir or what. I do notice when I unscrew the cap slowly while the truck is still hot, the level of the coolant will rise a good 1-2 inches in the reservoir tank, while the level in the overflow stays the same.
The upper radiator hose used to be really stiff, and stay that way overnight. Lead me to believe head gaskets went bad, but no other signs of HG were present… no oil in coolant, no coolant in oil, does not overheat, no blow-by or white smoke from tailpipe.
I started replacing all the cheaper stuff to see if those would Fix the issue, thermostats, hoses, reservoir cap and the radiator, but I had no luck. Then a couple weeks ago, I replaced the coolant tank itself. Since then the upper radiator hose doesn’t get as stiff as it used to get, and doesn’t hold pressure overnight anymore, but the same problem with low coolant in reservoir tank and too much coolant in overflow tank.
At this point I’m at an absolute loss, and can’t seem to find an answer anywhere online, and it’s getting quite frustrating. I appreciate all comments, and thank y’all in advance
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I do notice though, when I do add more to the tank and drive enough to lower the level, some coolant is added to the overflow tank. Not a huge issue, seems it doing it’s job as the coolant expands due to the heat, but eventually the overflow will fill all the way up and start leaking out the drain hole. I’m not sure if the overflow is supposed to eventually empty back into the reservoir or what. I do notice when I unscrew the cap slowly while the truck is still hot, the level of the coolant will rise a good 1-2 inches in the reservoir tank, while the level in the overflow stays the same.
The upper radiator hose used to be really stiff, and stay that way overnight. Lead me to believe head gaskets went bad, but no other signs of HG were present… no oil in coolant, no coolant in oil, does not overheat, no blow-by or white smoke from tailpipe.
I started replacing all the cheaper stuff to see if those would Fix the issue, thermostats, hoses, reservoir cap and the radiator, but I had no luck. Then a couple weeks ago, I replaced the coolant tank itself. Since then the upper radiator hose doesn’t get as stiff as it used to get, and doesn’t hold pressure overnight anymore, but the same problem with low coolant in reservoir tank and too much coolant in overflow tank.
At this point I’m at an absolute loss, and can’t seem to find an answer anywhere online, and it’s getting quite frustrating. I appreciate all comments, and thank y’all in advance
Sent from my iPhone using Tapatalk
