Hi. I have a 1998 Dodge Durango. I blew my water pump and i changed my lackey radiator at the same time. also replaced the thermostat. after that my durango went from funning at around 190 to a steady 140 degrees. dose not go any higher. i tried replacing the thermostat. nothing then tried a new cap. nothing. why is my truck not coming up to temperature.

 

What is the mixture ratio you're using? In winter months it should be 50/50 antifreeze/water and in summer months no more than 70/30. Typically I see this in the winter if you have too much antifreeze in your mixture.

FYI, its spelled heat.

 

50/50 i changed all my parts in the summer. and ran strait water and it still ran at around 140. i think it might be my radiator scene i got it at a junk yard.

 

What is the temp of the thermostat you got? 195 is stock and the lowest I'd go (and what I have) is 180*.

 

Did you bleed all the air out of your system?

 

Typically if you have air in the lines, it will run hot.

 

Did you install a Fail Safe thermostat? If so, you may have gotten a defective one. I had that problem a few months ago, the thermostat stuck open within a few weeks of installing.

 

+1

Had the same problem happen to me with it stuck open.

 

You need to take a temperature at the T-stat neck (upper radiator hose) to ensure the cluster is reading incorrectly.

Also, if you are running straight water you have no protection if it freezes or gets too hot (just so you know).

You could have a bad T-stat, did you test it before installation?

 

IR temperature gun works great for reading accurate temp at the upper hose.

Also, like hydra said, running straight water isn't the best way to test it. I misread it but now over reading it, you can't take a good temperature test with straight water.