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5.8L running hot?

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  #16  
Old 06-16-2015, 11:42 AM
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More than once there has been a bad thermostat right out of the box...sometimes multiple bad. Time to verify the thermostat is operating correctly.
 
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Old 06-16-2015, 11:46 AM
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250 is redline on the factory gauge, so yeah she's running hot.

How old is the water pump? How's the coolant flow?
 
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Old 06-16-2015, 03:17 PM
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Original water pump, but it has good strong flow. I have a feeling this warm temperature stuff has been going on since before I had it. I was maybe thinking about going with a clutchless fan but I'll check the thermostats first. One question if the current thermostat is functioning correctly, will putting a new lower temp unit have any effect on the engine temp? Or no since the current thermostat is already open all the time?
 
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Old 06-16-2015, 06:27 PM
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Originally Posted by JimiLL
One question if the current thermostat is functioning correctly, will putting a new lower temp unit have any effect on the engine temp? Or no since the current thermostat is already open all the time?
Any attempt to use a lower temperature thermostat is a bandaid fix to mask the root cause.
 
  #20  
Old 06-17-2015, 02:24 PM
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Is it filled with coolant water mix or just straight water. I would imagine if its straight water it'll run hotter but the proper mix will be cooler.
 
  #21  
Old 06-21-2015, 12:34 PM
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I just re read a earlier post and noticed I accidentally said the trucks runs 250-210 degrees. I meant to say 205-210. I think 210 is still a little warm but you guys know better than me. Testing thermostat as I type now
 
  #22  
Old 06-21-2015, 12:35 PM
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Also truck runs 50/50 coolant water mix
 
  #23  
Old 06-21-2015, 12:47 PM
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Just tested thermostat. According to my digital meat thermometer, thermostat did not start to open until around 203 degrees, which is aligning with what the help gauge in the truck is saying. I'm going to get a thermostat now, ill test that one then install it.
 
  #24  
Old 06-21-2015, 04:23 PM
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Ok bought a new 180 degree thermostat from advanced auto. Tested it before installation and it didn't seem to start opening until around 190 degrees. One installed the truck now runs near 190-195. What gives these thermostats seem to open about 10 degrees late.
 
  #25  
Old 06-22-2015, 03:33 PM
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Originally Posted by JimiLL
Ok bought a new 180 degree thermostat from advanced auto. Tested it before installation and it didn't seem to start opening until around 190 degrees. One installed the truck now runs near 190-195. What gives these thermostats seem to open about 10 degrees late.
Weird. Where is the gauge now out of curiosity? I don't know what temp thermostat is in my truck but it has decent heat and doesn't leak so I'm going to leave it alone for now. However my gauge is hardly ever even hitting the O in NORMAL. If it idles on a 90 deg day w the AC on for a period of time it will hit the O but after you take off again shes right back down to N.
 
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