So I have a 2011 ram with a 5.7. My cooling system has been acting up in the last few days. I changed the thermostat about a month ago when I had these exact issues and all was good till now. Sometimes my coolant will run to hot, it'll get up to about 230 degrees, and I'll have to slow right down to let it cool off a bit. Or sometimes it'll have issues getting up to and staying at operating temperature, it'll hop between 185-200 degrees. I just tried a new 203 degree thermostat, thinking maybe I got a bad one but it's still having the same issues. I had a 16 PSI rad cap and put on a new 18 PSI one but that didn't change anything. One day it'll run to cold, the next day it'll run to hot. After I put this new thermostat in today and went for a drive, it got to hot (220) so I parked it and noticed my top rad hose had collapsed right when I popped the hood, so I cracked the rad cap and let it expand and once I got going again it wouldn't get up to 203 degrees... I'm stumped. Any help would be great !
A collapsed hose will cause it to get hot. I would change both hoses and see what happens. May do a drain and back flush? How does you coolant look, discolored at all?
another thing I just found by googleing the problem of a collapsed hose is that your hose to the overflow bottle may be blocked.
I'm pretty certain the overflow isn't blocked and the heating issues isn't coming from the collapsed hose cause that's the first time it's collapsed so far. My coolant is in good shape, I'm considering flushing out the system anyhow though, maybe I do have some gunk somewhere. I'm also wondering if I just got a bad thermostat or have an air lock.
Another thought, I had a water pump lose all its fins once and had an overheating/heat problem. Ended up cracking my head (4.0 six cylinder) Try running with the cap loose and see what happens.
I was thinking water pump as well, but if it was my pump I wouldn't also be having the issue of to little heating. I'm driving right now and I can't get up to operating temp.
But sometimes it's getting too hot as well. I did get a new thermostat again. I'm gonna drain all the coolant and flush the system shortly and refill it with new coolant and pop in the new thermostat.
Changed out the thermostat and filled the system with new coolant, the truck had a really hard time getting up to operating temperature and when it did it only stayed there for a moment.