water temp parameters (limit)

[19Kgvw]

Picked up this 2018 3500 6 months ago to replace my 1st GEN that I had a long time.
So - question about water temp spread. After warmed up (30 mi drive) the engine water temp could be 165...180 ish.....and up to 204 deg. the 195 and above is normally while towing weather the outside temps are in the 40's or 90's.

I'm guessing that there is a 180 water thermostat installed and so water temps from 180-190 would be normal. and while at the 180-190 temps the guage is 1/4-1/3 scale. When the temps get to 204 the dash gauge is just below 1/2. The aux fan is not engaged yet at the max 204 deg.

What is the standard op temps and what is the max water temp? My old 93 only had the dash gauge and it was really rock solid at 1/4 scale unless the temp was upper end and the overdrive fan was on.
Am I just overthinking this topic because I can actually see the digital actual coolant temp?

thanks - rich

 

[19Kgvw]

And........
1- at what coolant temp does the aux override fan spin up ?
2- and I just realized this is in the wrong section - please move if needed.

Rich

 

[sag2]

My 18 runs 190-205, up to 220+ when towing in 100° + weather. You can hear the fan kick in around 215-218, then temp drops , then cycle repeats. I don't recall it ever going over 225.

 

[19Kgvw]

My 18 runs 190-205, up to 220+ when towing in 100° + weather. You can hear the fan kick in around 215-218, then temp drops , then cycle repeats. I don't recall it ever going over 225.

thanks SAG2...... exactly was I was looking for.

 

[AH64ID]

You should have a 190° thermostat, if it runs much cooler after warmed up then I would replace the thermostat.

Empty crusing should be within a few degrees of 190°, but the EGR cooler can make it slightly higher in around town driving.

The thermostat goes full open at 207°. I pull post hills around 215-218°, and haven’t seen 225°.

Cummins says 225° is the max allowable temp for the 190° thermostat and Ram says 245° is the max temp.

The fan starts to ramp up at 207°, but really gets going at 217°. Max rpm, 4000, is at 228°.

 

[Diesel85]

The work 2020 I mostly drive around in does between 188F and 195F empty.

I've always assumed the truck was fully warmed up at 190F.

I have gotten up to 215F a few times towing the skid steer during the summer when it's 85F. Engine fan was running good.

 

[Tuesdak]

I'm guessing that there is a 180 water thermostat installed

Or the OEM one is cracking open early or jammed slightly open from some failure, debris, or wear. Even fully closed in some winter conditions you may need the winter front installed. You haven't mentioned location or outside temps. How many miles on it?

Use a Genuine Cummins or Mopar part. The cheap from parts stores is reported to not work so well. But first I would test the one you have to be sure it's the problem. It may also be marked with a temp or part number.

 

[19Kgvw]

Or the OEM one is cracking open early or jammed slightly open from some failure, debris, or wear. Even fully closed in some winter conditions you may need the winter front installed. You haven't mentioned location or outside temps. How many miles on it?

Use a Genuine Cummins or Mopar part. The cheap from parts stores is reported to not work so well. But first I would test the one you have to be sure it's the problem. It may also be marked with a temp or part number.

miles on truck is 87K....
UPDATE - thermostat finally failed all the way - stuck open. Replacing thermostat which will bring the engine back to normal all the time.