my 2000 durango is overheating but only on the highway recently replaced water pump and t stat oil looks good coolant still good any one else thinking clogg in the system

 

does that have the radiator outlet at the mid point? and when was the last time you pressure flushed the cooling system?those half way up outlet radiators need a good flushing=sediment from the engine ie rust crud can settle in the bottom
also replace the thermostate and the radiator cap=sometime the cap fails and it doesn't hold the 16lbs of pressure..
coolant ratio? 50 to 50 water to coolant?
one more thing did you bleed all the air outta the system=air pockets can cause overheating...

 

Take it to a car wash open the hood and spray through the condenser on the front end and also spray the radiator from the engine side by the fan. We have had problems with just debra in the fins.

Now the clutch fan could be out. If it overheats in the city this would make sense but on the freeway more air gets through so overheating isn't as bad.

Check the clutch fan.

 

flushed the system when i replaced the water pump and t stat
i will check the cap still think its odd one day its fine driving 100 mile round trips at 85 mph and then it cant take 10 minutes at 75?

 

will check debre too

 

10 min at 75mph sounds more like a air bubble so burp the system.

Did you check the T-stat before install? I've seen more bad ones then I dare to say.

Could have installed a bad pump. Where did you get it and I hate rebuilds?


The 4.7L's can have a very bad burp problem but for some reason I thought you have a 5.2L

 

What about a radiator cap? I guess some years really don't have them but if your does I would replace it.

 

Yup,I forgot 4.7's have that funky radiator..Hey ,where can I get a Debra stuck in my radiator and will she still be in a good mood when I het her out?---sorry couldn't resist

 

cap looks real old and i notice there is little particles of rust in the system will reflush the system and clean radiator i have to go on a long trip tomarrow to my new huse in west bookfield 1.30 minutes away hope i can fix my truck i wanted to take it 4 wheelin

 

In the morning, even when below 50deg, my fan clutch is engaged for over 5 minutes when I leave my house to go to work. It's making noise and wasting gas when it shouldn't be. But it cools good.
Geez!
So, if anyone has a worn out fan clutch, I'll trade you for a good one.