[wennis1]

At a stop light or in traffic my truck temp rises from 165 to 200 and sometimes 205. If I run on the freeway it goes back down to 165. Does anyone know why it does this? Also, how do I flush the radiator? Any suggestions would be greatly appreciated. Thanks

 

[can17]

Here's how I flushed the radiator/engine:
After draining the coolant from the radiator (this is also a good time to remove and clean the radiator) disconnect the upper radiator hose from the radiator. Next remove the thermostat from the motor and replace the upper hose on the motor. Then fill the radiator with a garden hose through the hole that the upper hose connects to. Start the truck, and continue to fill the radiator with water while the water pump cycles the water through the radiator, the engine, and then back out the upper hose. I would flush for at least a few minutes.

 

[mhenon]

Sounds like your thermostat is sticking. You can probably get a new one from NAPA and the swap is simple enough.
Mike

 

[RJF]

Sounds more like a bad fan clutch. When you are at a light, there isn't any air flow going through the radiator, causing temps to rise. At 70mph, you are getting enough air regardless of what the fan and clutch is doing.

How well is your A/C working when parked? If it sucks parked, but works fine traveling, then that is also a sign of a lack of air flow from the fan.

Check your fan, if it has no tension when you try and turn it, it's likely bad. Also, if the clutch looks like there is oil on it, then it's definantly your problem.

 

[Mopar1973Man]

202*F to 205*F is normal for traffic...

I change my coolant every spring and change my thermostat everytime. My normal temps in traffic are about 200-205*F with the A/C on... But the running temp should level out about 195*F normally... If its falling down to 160*F I would say the T-stat is shot.

Take notice to the temp on the bottom of the t-stat...

 

[pblankenship]

Check your air filter too. I am sure that you don't run around in dirt like I do, but I know that I am having breathing problems after being out in the field.

 

[wennis1]

Thanks for all of your replies. I'm sure that will keep me busy all weekend. By the way, I have never flushed the radiator or done anything with the cooling system and the average high temp has been 165 to 170 since I bought it new.

 

[DodgeCummins98]

I think you need a new thermostat. While 205 is pretty normal in traffic, it should not drop to 165. Operating temp is about 190.

 

[DodgeCummins98]

Hmm, maybe I should have read Mopar's post. :lol3: He said the same thing.

 

[Mopar1973Man]

Hmm, maybe I should have read Mopar's post. :lol3: He said the same thing.

:rof Dang i thought I was bad some days... I even posted pictures...:rof:thud::w: