Was just looking around today and was scrolling through my coolant temp and the truck was steadily running 82-84 celsius. Pretty much right round 180 degrees. I noticed online that the 6.2 has 2 different thermostats available. 195 and 180, do snow plow prep trucks come with the lower t stats? Mine has the plow prep package, and is used to plow with. Just wonder what qualifies a truck for the lower t stat

 

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I do not know this as FACT...

but the 180 is for service where 100 plus degree weather is common..
not the other way around.

 

Im curious to know. I had custom ordered my truck and have had it since new. Delivered to Long Island, NY. Going to have to take a look at a few of my friends trucks, all 6.2s with plow preps on them.

 

I know 195 has been common since fuel injection became common..

 

 

180 deg. is an option for all engines, but all newer EFI engines all come with and sensors are designed to work with 192 deg. or 195 deg. thermostats with very few exceptions. I would stay with the 195 deg. as that is what came from the factory on all 6.2L. Their have been many study's done and the it is a proven fact that a 195 deg. thermostat will cool better than a 180 deg. because it slows the coolant flow down to allow better heat transfer. Don't believe me google it. I didn't believe it either until I read up on it.

 

That's largely a modern myth. Faster coolant flow will obviously reduce saturation time BUT you're exchange rate is higher, so the BTU/ hr. is the same. The only argument in favor is the 195 is the increased differential between coolant temp and ambient air temp. Since the delta rate is exponential, the hotter coolant will shed more degrees in a given period of time, but it was hotter to begin with, so the discharge temp at the radiator outlet is nearly identical. The difference is practically nothing, maybe a couple degrees. This theory has been popping up for decades.

 

 

My truck runs 195 in the summer and 180 in the winter (unloaded). So, you very well have a 195.

 

 

my transmission takes a long time to warm up seems like.....
and it has a thermostat

 

as it should... its not working hard... unless towing heavy...

engine makes its own heat by burning fuel to run... gas burns in an engine at about 800 degrees..
transmission makes heat by rubbing parts with fluid.. converter the most.. so in the cool.. takes some time..

 

The tranny runs a LOT cooler in the winter and when lightly loaded. I'll bet that that is part of why mileage goes down in winter.

 

Actually gas combustion temps are far higher than that. If you have a pyrometer on there, you can see that EGTs are around 1600 degF on the exhaust side. Diesel engines run a bit cooler, around 1350F or so.
Gasoline itself has a vapor point around 600F and can self-sustain burning a bit above that. But the typical operational temps in an engine combustion chamber are far higher than that minimum temp of sustained combustion in a lab experiment.

Part of the disconnect of this topic in terms of the heat in an engine is exactly where you want to debate the temps are taken. Whereas gas engine EGTs can be 1500F, the header manifold isn't that hot, as it the ability to air cool along it's surface. The cylinders and pistons do not sustain 1500F, because that is only the temp of the exhaust charge immediately after combustion and upon exit of the cylinder. Don't forget there's a cool intake charge incoming on the next downstroke! So the cylinder/piston temps AVERAGE much lower than their peaks.


Also, I echo the topic of the t-stat and radiator. This is a topic of thermal heat exchange, not just some temp of a mechanical device. Any engine can either run hot or cold, depending upon many factors. T-stats are devices that are supposed to hold a MINIMUM temp, not a maximum. If the load is great enough, and the heat exchange system (pump, fluid, surface area, airflow) is too small, any engine will overheat. Conversely, if the load is low enough, and the system not set properly, an engine may never come up to temp.

I once had a 1987 diesel Escort while in college. In the winter one cold day, I barely got it to start up. I let it idle in the driveway for more than an hour, and the temp never rose enough to even move the needle off the "cold" mark. This is because not enough energy was being consumed to even heat the coolant. It was essentially sustaining enough energy to keep the combustion process continuing, but it was loosing heat via the block and manifold surfaces at a rate fast enough that the radiator was moot, as the t-stat never even had to open!

Honestly, I prefer my engines and trans to run right around 200F or so. That's the right temp to find the balance of safe operation and proper fluid temps. Oil actually does it's job best at full temps, as designed. For me, the Goldilocks approach is to have my engine between 200F and 215F, and the trans also.

There was a time when it was believed that cooler was always better when it came to trans temps. This is due to the way older trans fluids would oxidize with heat. But today's lubes are not nearly as sensitive to temps like that. The age-old addage of every 10degF of temp drop doubled your trans life was based upon old data that just does not apply any longer. There was no data to prove that true; it was just an estimate based on the rate of progression of the oxidation of old tranny fluids.