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Asian_Male;5276229
> IF your ATF is measuring at 300 degree Fahrenheit, something is wrong.
LOL! TRUE!!!
> The idea of the radiator with ATF going through is that it's a heat exchanger. As 200 to 225 degree ATF is coming out of the transmission, the radiator fluid at 180 - 200, and the fan pulling heat away, helps to dissipate the heat and bring the ATF temperature down.
Sometimes cool it - But I expect the coolant to be at 195+ in rather short order, and to often be around 220-230... The radiator can also warm a tranny in a cold climate. But thanks for the added info.
Sometimes cool it - But I expect the coolant to be at 195+ in rather short order, and to often be around 220-230... .
I have a Scan Gauge. It reads the engine coolant temperature from the OBDII port. My driving conditions are such that on the freeway, the coolant is about 175. On city streets, with stop and go traffic, I see up to 200.
The transmission temperature from the OBDII port shows an average temperature around 200. Sometimes it's 190 - 200. Sometimes it's 200 - 210. I have seen seen up to 225 - but rarely. But it all depends on driving conditions. Sometimes I can drive across town, and the transmission temperature is only 160 or 170 at the end of my trip. Just something to think about with a fluid cooler bypass valve that is open until 180. In theory, at 180 degrees, the valve closes, then ATF flows to the cooler. The coolant helps relieve the ATF, and the fan draws heat away.
Keep in mind that these trucks came in a lot of configurations. Different engines. Different gears. Different wheels and tires. And then, a lot of trucks are not as they were built at the factory. My own truck has a lift kit, 35" tires, 4.10 gears, and is running a custom tune. So my results will be different.
You can install a thermostat which opens at 160, and electric fans programmed to turn on at 180. You could also delete the transmission cooler bypass valve. Most people would not recommend it. Nonetheless, lower temperature thermostats exist. Electric fans can be programmed for different temperatures. Not that hard to remove the transmission cooler bypass valve, and install transmission line in it's place. These trucks are designed to operate at maximum efficiency with the operating temperatures around 200. Which means the truck is most fuel efficient with temperatures from 175 to 225.
And after driving all day, all in stop and go city traffic; it means that I have a gauge device which gives raw data and the data is not all that useful. The only thing that I can extrapolate is that the truck is not overheating. Maybe I didn't need a gauge to tell me that.
