i have a 2001 dodge dakota with the 4.7 it runs fine it just starts to slowly overheat after about 10 to 20 minutes of driving around the owners before me put stop leak in the radiator could it be clogging the system up?

 

yes, especially if its plugging up your thermostat and not allowing it to open......

probably should flush it too, what color is the fluid? does it look pretty or does it look rusty/dirty, or is it only water?

 

I purchased my truck with an over heating problem too, come to find out the thermostat went bad, the radiator was leaking and there was some coolant that worked its way into the motor oil. In my case I of course dumped the coolant, new thermostat, new radiator and then decided to replace to head gaskets because I intend on keeping the truck a long time and an oil change. It has been 4k miles since this and never a problem

 

it was like green mostly water though... i just flushed it and put new coolant in it and drove around it seemed to help but i havent drove it on the highway yet.. i just bought this truck three days ago when i test drove it everything was fine i drive it 75 miles home 5 miles from the house it starts overheating but it never went in the red just right below it ill see if it overheats tomorrow on my way to work

 

Stop leak is not meant to cure leaks forever its meant to be used when you are in a jam just so you can get the truck home or to a shop. It should be flushed asap. Stop leak clogs the rad and heater core it does nothing but cause problems in the future. The last owners that had my buddys jeep put it in the rad even after the new one was installed it started to clog it up my buddy has flushed the engine and rad 4 different times so far and it still isnt right overheats when going under 20mph

 

i had the same problem with mine everytime i thought i fix the problem it would over heat again and it was actually the head, so check that