Hey guys. First post, hope you can help me out. I have an 03 dakota 4.7 with 86000 miles on it. I was running way to hot while sitting in traffic. Now I am overheating all the time. My lower radiator hose is bulging when hot and my upper is cool. I replaced the thermostat but it didnt do anything.

 

Sounds like a circulation problem. Check radiator. Could be clog.Also look at the top water pump at the sip hole for any coolant.

 

something thats rare but the lower hose may be separated inside, and is blocking the water. if it was mine i would replace both hoses. and before you put new coolant in, put in 8-10 oz of marvel mystery oil, will stop rust. some guys use 160 or 180 stats to get power. but i think that might reduce engine life. so for street driving i like 200 205 stats, for linger life.

 

what does your gut tell you the problem is???

 

Not sure. ive heard that the water pump goes in the 4.7s. getting it to a shop today. id do it but i have to work

 

so i took it to a mechanic (only cause i have to work). he said my radiator cap was holding no pressure. i havent messed with cooling systems at all. could this be whats wrong?

 

A bad cap can lead to overheating but if you have a lower house that is bulging you'll need to address that now. If it bursts you will overheat quickly and the 4.7 doesn't like to overheat. It gets very expensive very quickly.

Water pumps fail on any engine, not just the 4.7.

 

Yes. But like 00DAKDan said still would be a good idea to change lower hose. Not that expensive and the 4.7 are heat sensitive.

 

I'm replacing the lower hose, but I'm starting to think its not the water pump. was told usually they fail at the bearing causing them to leak. really hoping that it is just a cheap radiator cap.

 

Ha, all it was was a radiator cap. Wish i knew that before I brought it to a garage. O well. I'm just glad its fixed.