Okay. I've got my 4.7 V8 Durango. 2004. It runs just fine. Everything on it... is just fine!

Well, except that it overheats sometimes. It pretty much only happens after we've slowed or stopped after a long drive. Today, for example, we got back from a trip that involved about an 11 hour drive. But it doesn't always happen like that. It was 13 hours to get there, and it was fine. So what happened today on the way back?

Here are some details:
Before, it would occasionally pop the overflow bottle and a bunch of coolant would rush out of there. Thinking the radiator cap was sticking, I replaced that, and everything has been pretty normal after that. On the way home, the temp was reading normal and everything was running just peachy. But after we got home and unloaded everything, I had to run out again to do a couple of things. It was then that I noticed the temp shooting up just a couple of miles down the road. ??? I pulled over and popped the hood. The upper radiator hose had blown and sprayed water all over the place.

I replaced the hose yesterday and everything seemed to running fine after that. But today, it runs rough when cold, then seems to be normal after it warms up. The check engine light came on earlier, and I'm heading over to the auto parts store in a little bit to get the codes pulled (I couldn't get them to come up doing the key thing).

I have my theories as to what might be wrong, but I want to see what other folks think.

Ideas? Suggestions?

 

I would replace the stock thermostat with a low-temp (180 degree) one and flush the radiator. The coolant should be replaced every two years. Post the codes or you can obtain them through the odometer by turning the car from off to on (not start) three times,
FF

 

you CAN replace the thermostat to a lower 180* one, but on the 4.7 we dont usually recommend it(because the stock t-stat on the 4.7 has a weep hole on it which is necessary for the cooling system to work correctly), that is more for the 5.2/5.9l engines(from the first gen trucks), the upper radiator hose went out, did you change the lower one? did you use a factory hose for the upper (the factory hose has a spring inside to help keep it from collapsing, aftermarket ones dont always have this), also are both your fans working? the efan against the radiator, and the clutch fan closer to the engine? (clutch fan should spin no more than 1/2 a turn by hand w/ the engine off) it sounds to me like the thermostat is fine since you had an 11 hour drive w/o overheating, did you burp the system after replacing the hose?

also get us those codes, it will help us narrow it down

https://dodgeforum.com/forum/1st-gen...-problems.html
https://dodgeforum.com/forum/1st-gen...hermostat.html

 

I'm on my phone, so forgive any fat finger errors.

Ok, the only code is P0300. I think that's multiple cylindar misfire. I imagine that might be from coolant spraying all over the driver's side of the bay.

I didn't burp, but I will when I get home. And I used an aftermarket hose. Didn't replace the lower.

 

Random misfire code.......maybe a tune-up with a change of sparkplugs is in order,
FF

EDIT: link for P0300 truoble code

http://www.obd-codes.com/p0300

 

I came home and burped it tonight. It seemed like bubbles were coming out of there for forever! But they eventually stopped. Both fans work. The main one by the radiator is driven by belt and always runs. And the electric one on the driver's side (what's that for?) comes on here on occasion.

I have to admit: I'm paranoid that it's a blown head gasket. I was convinced that was it, but I'm not so convinced after pulling the code earlier. I imagine a blown or leaking head gasket would cause just one cylinder to misfire. Any opinions on that one way or the other? I honestly can't afford to replace that.

Speaking of misfire, I drove it tonight after burping it. It definitely misses here and there, but not consistently. Sometimes it won't miss at all. It's definitely more noticeable when hitting the gas.

Think the random misfiring is due to coolant spraying all over when the hose burst earlier? Maybe it just needs to dry out? I noticed some coolant pooled in a couple places.

 

The oil on the dipstick would look milky (think of coffee with cream) if the head gasket was blown,
FF

 

So.... I checked it again this morning. Started up just fine. No missing or anything.

I checked...
Coolant: no oilly stuff or froth, etc.
Oil dipstick: looked like oil. No water or coffee.
Oil cap: nothing

I reset the computer and revved it. No misses and no new warnings. I drove it to work and it ran normally both cold and warmed up. The only thing I noticed was that it seemed to hesitate if I really got on the gas. I'm going to check for vaccuum leaks tonight. Anything else anyone wants to suggest? I'm leaning away from head gasket issues at this point, but I'm not ready to put that away yet.

Maybe I should start a new thread. I don't know if this qualify's as an overheating issue anymore.