StevensWMR
OBS Enthusiast
Okay I need to explain everything so all info is there.
2000 K2500 5.7l 4l80e
My truck had a 160* thermostat since purchased. I replaced the radiator appropriately 1.5-2 years ago.
Well a couple weeks ago my thermostat hung closed AND my water pump (likely factory) started pouring out water and my truck overheated on the highway. I say that, I saw the temp gauge max out to the red mark so I killed it and coasted to the shoulder. I let it cool down for a couple hours and I filled up radiator and drove it home. (Wasn’t very far)
I installed new water pump and a 190* thermostat after learning that is what is it should have anyway and is recommended and have noticed a large increase in overall performance and mileage since then.
Now that being said, I have asked everyone I can, mechanics/400 owners/etc. and my temp gauge should read 190-200 mostly. My dad says his 6.0l stays around 210-220.
My truck stays at 225-240. If I blast the heater it will stay around 225 on highway and when idling or if I use AC instead of heater it goes to 245-250. At first I thought it was overheating again and would pull over let it cool and notice low on water. I fill back up but every single morning I have to add 2.5 bottles of water. No leak visible!!! But as I add water it won’t stay topped off. It lets out air bubbles and steadily drains down the maybe 1” below the filler neck. After 7 or so times I top off it will stay up there but still releases tiny bubbles. Is this just air in radiator or is that show a leak somewhere? Didn’t drip water though I have watched it like paint drying. One of these times I popped the hood and boiling water was coming out the sides of the radiator cap!!!
Thought new thermostat wasn’t opening so put in a second new one. Also put a new radiator cap. Still losing water. There is no water in the oil. However today I pulled over to let it cool since it was on 235 with heater on for about 30 miles. I squeezed the top hose to see if there was still pressure and squeezing it felt all crunchy. I took it off and ramrodded something through it and cleared out a crap load of black tiny pebble things. Could this be coming from my radiator? Or going into it and clogging it up? Causing it to run hot and discharge water while driving from the over flow or cap? OR is it possible I damaged head gasket and losing water that way? However no water in oil and I don’t see a leak anywhere on the block.
Also note that the water that goes into the overflow from the radiator is brown and dirty looking. Could this be that rocky stuff like in the hose or possibly oil going into the water instead of vice versa. I have a bad rear seal so can’t tell if I’m losing oil that way.
2000 K2500 5.7l 4l80e
My truck had a 160* thermostat since purchased. I replaced the radiator appropriately 1.5-2 years ago.
Well a couple weeks ago my thermostat hung closed AND my water pump (likely factory) started pouring out water and my truck overheated on the highway. I say that, I saw the temp gauge max out to the red mark so I killed it and coasted to the shoulder. I let it cool down for a couple hours and I filled up radiator and drove it home. (Wasn’t very far)
I installed new water pump and a 190* thermostat after learning that is what is it should have anyway and is recommended and have noticed a large increase in overall performance and mileage since then.
Now that being said, I have asked everyone I can, mechanics/400 owners/etc. and my temp gauge should read 190-200 mostly. My dad says his 6.0l stays around 210-220.
My truck stays at 225-240. If I blast the heater it will stay around 225 on highway and when idling or if I use AC instead of heater it goes to 245-250. At first I thought it was overheating again and would pull over let it cool and notice low on water. I fill back up but every single morning I have to add 2.5 bottles of water. No leak visible!!! But as I add water it won’t stay topped off. It lets out air bubbles and steadily drains down the maybe 1” below the filler neck. After 7 or so times I top off it will stay up there but still releases tiny bubbles. Is this just air in radiator or is that show a leak somewhere? Didn’t drip water though I have watched it like paint drying. One of these times I popped the hood and boiling water was coming out the sides of the radiator cap!!!
Thought new thermostat wasn’t opening so put in a second new one. Also put a new radiator cap. Still losing water. There is no water in the oil. However today I pulled over to let it cool since it was on 235 with heater on for about 30 miles. I squeezed the top hose to see if there was still pressure and squeezing it felt all crunchy. I took it off and ramrodded something through it and cleared out a crap load of black tiny pebble things. Could this be coming from my radiator? Or going into it and clogging it up? Causing it to run hot and discharge water while driving from the over flow or cap? OR is it possible I damaged head gasket and losing water that way? However no water in oil and I don’t see a leak anywhere on the block.
Also note that the water that goes into the overflow from the radiator is brown and dirty looking. Could this be that rocky stuff like in the hose or possibly oil going into the water instead of vice versa. I have a bad rear seal so can’t tell if I’m losing oil that way.
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