My truck runs 185 on the hwy at 60 MPH regardless of weather but on a 600 mile trip back to Florida I noticed in 95 degree heat running 80mph it sat at a steady 195.

Thoughts? Granted running at 80 is working the motor more than lower speeds

 

More speed & more heat with no real increase in air flow thru the tiny Grill/Radiator.

I’m seeing 188-211F right now in lovely SETX. With temps in the 90’s 100% humidity, AC on full blast, and 65-75MPH. Not all concerned. It’s 215F and not dropping that I’d be curious about.

D2’s with a stock OEM style thermostat will rise & fall temp wise. On long trips I see all my D2’s (with OEM style thermostats) rise & fall over time. If it was just one out of my 3 D2’s I’d be suspicious, but they all do it, 99, 02, and the 04.

 

@Ben Matheson That is what I see on mine too, it sits at 183ish at 60 mph below 25 deg C then runs up to 188 -197 as the temps get above around 28 deg C. Long steep up hills do the same, but it drop once I clear the summit.

 

I’ve seen as low as 136 downhill in the mountains and as high as 215 sitting in Denver traffic when it’s over a 100 out with AC on

Usually at 190-194 without AC

i have inline setup with 180 tstat

 

Thanks guys I'm feeling pretty good about the old girl. In the last 2 months I've done 4 600 mile trips and she's run like a champ and 2ft deep river crossing without the dash lighting up. Got to use CDL in the mountains and downhill assist.

Pretty pleased at this point

 

Yep she sounds good to go to me! I truly enjoyed my D2 at last years 2018 HCRR & it was SO much more enjoyable to drive off road vs any of my setup Jeeps. Manual Mode, TC, and HDC worked flawless.

 

CDL made some pretty steep muddy roads feel like i was driving on pavement. I do believe you could drive this thing up a tree and down the other side LOL

 

I’ve been wanting to ask the same question re: my temps - and more less confirming my thoughts.

Truck had paperwork & I spoke to owner of garage who regularly services the truck thru out it’s life with previous owner. I got into the truck as it came out of shop from head gasket & radiator replacement. - I was steady at 184-188 occasionally 194 highest.
This was just after I did in line mod 125k mi on clock

8 months ago I exploded my rear carier & while I rebuilt, I changed my gears to try 4.47’s.
i still keep rpm in around 2000-2500. So
going slower, and just this summer swinging temps above 194 - 206, 208. Now 196k mi. Where I was not seeing this previously.
Curious life expectancy of a Nissan radiator or original fan clutch. Water pump replaced within 10k miles.