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**Gregski** · 02-03-2018, 09:28 PM

So what are the findings?

So now with a brand new stock 195* thermostat, a brand new short water pump, a brand new plastic/aluminum radiator, running water only (for test purposes only)...

The truck idles fine in P-Park I think it was like 135* F after 15 minutes of just sitting there, it would slowly warm up more, but I decided to take it for a spin

It cruises at 185* F, however and here's what I recently discovered, when stopped at a stop sign or at a stop light, it will climb North of 200* F in just one minute, now this is in D as in Drive

OK, yeah so what? Well I decided to shift it into N for Neutral and sat at an isolated Stop Sign for five minutes and the truck never inched past 195* F, now that has to tell us something! Right?

I also tried it in reverse, I pulled into a parking lot and backed into a space and left the truck in R-Reverse and sure enough in just one minute it reached 200* F

your thoughts?

02-03-2018, 09:28 PM	#84
Gregski Post Whore Join Date: Aug 2014 Location: Sacramento, CA Posts: 10,803	Re: 71 350 running hot coolant backup up problem So what are the findings? So now with a brand new stock 195* thermostat, a brand new short water pump, a brand new plastic/aluminum radiator, running water only (for test purposes only)... The truck idles fine in P-Park I think it was like 135* F after 15 minutes of just sitting there, it would slowly warm up more, but I decided to take it for a spin It cruises at 185* F, however and here's what I recently discovered, when stopped at a stop sign or at a stop light, it will climb North of 200* F in just one minute, now this is in D as in Drive OK, yeah so what? Well I decided to shift it into N for Neutral and sat at an isolated Stop Sign for five minutes and the truck never inched past 195* F, now that has to tell us something! Right? I also tried it in reverse, I pulled into a parking lot and backed into a space and left the truck in R-Reverse and sure enough in just one minute it reached 200* F your thoughts?