So here is the situation. The recent heatwave, 115 degrees to be exact hasn't done any favors for the truck. I noticed it yesterday when she got pretty toasty. Gauge read 230 so I parked her. Barfed about a water bottle of coolant out the overflow. Threw in about 2 gallons total of coolant/water mix. Acted fine for about a day (gauge never saw over 195). Started again today, same problem. There is no pool of coolant under the truck where I park it, cept for what is spit out of the overflow. Changed the oil, right as it should be, no cloudiness. When it barfs, the coolant isn't odd colored, just greenish. so no blown head gasket. The heads arn't even a year old and brand new, not rebuilt when i put them in. Hope they arn't cracked. My only question is where in the hell did the 2 gallons of coolant go in 14 hours? There is no signs of leakage ANYWHERE. No smoke from the tailpipe. My only theory is that the thermostat is stuck closed, and is only opening by the pressure from the system, and when it re-enters the radiator, it takes the easy way out, through the overflow until there isn't enough left. But I only smell coolant when it pours out the overflow when I park it. Removing the thermostat monday, and im gonna boil it to see if it opens. The thermostat isn't even a year old. Thought i'd run it by you guys.

 

Test your radiator cap as well.

That much coolant HAS to be going somewhere........ Take a whiff of your exhaust.... see how bad it smells.

 

ill do that. Rad. cap isnt a year old either lol

 

Just had this issue with a 96 ram, 190,000 miles, it was the radiator.
Found this out after 3 thermostats, fan clutch and water pump had all been replaced.


Dave

 

yeah, thats the next thing if this isnt it

 

I'm going to say radiator for sure.

Do the simple stuff first to make sure. Check your T-stat as it really ain't hard, you could try a new rad cap but I don't think it is going to be it. I've done enough cooling system work on my Ram. Sounds just like what happened when my radiator was bad.

 

Check the cooling system with a pressure gauge to see if it holds. And if it doesn't hold, you can see if it's coming out of the rad without evaporating.

 

I got the same flipping problem... overheated last week put in a new thermostat... next day the darn bypass hose blew... now today it is overheating again... rad is only 3 yrs old... not loosing coolant, just HOT...

Clutch fan?? how do I know it is working right?

 

Does the truck run cooler going 45+ mph? If so, the fan clutch could be going out. At 45+ mph, there is enough air forced through the grille from driving that the fan clutch isn't needed to pull in air. If you have a bad fan clutch, your truck will overheat at low speeds and idle. A partially clogged rad can cause similar symptoms, so if you replace the fan clutch and it still overheats, I'd be looking at the radiator next...