Engine/Transmission (1998.5 - 2002) 180° stat, raised transmission temps.

[Big White Beast]

I recently installed the 180° thermostat and have been watching the gauges a lot. I know the weather has been warmer but it still seems like my transmission around town will get hotter now. Only thing I can think of is the fan isn't running so it doesn't draw air past the transmission cooler.



Yesterday was the hottest it's been and the engine temp actually raised past the 180° mark. Didn't quite hit the 190° mark where it used to sit but did go up. At what temp is the fan supposed to kick on. I've never really noticed it like some people claim. Then again my truck is noisy and I turn the radio up to drown it all out.



Is there an electric fan that just mounts over the transmission cooler portion? I could toggle it on around town on those hot days.



Any thoughts or am I paranoid!!



Garrett

 

[Pit Bull]

Originally posted by Big White Beast

I recently installed the 180° thermostat and have been watching the gauges a lot. I know the weather has been warmer but it still seems like my transmission around town will get hotter now. Only thing I can think of is the fan isn't running so it doesn't draw air past the transmission cooler.



Garrett

Garrett, your observation makes a lot of sense. I have the 190 degree. Even with my loud engine and the radio up you can tell when the fan comes on. It roars.

 

[Big White Beast]

testing

Is there a static test to see if the fan clutch is working? Honestly, I've never noticed it turning on. Then again I never really paid attention. The way some of you make it sound it can't be missed.



Garrett

 

[Big White Beast]

Never mind.......

I quit being lazy and got out the manual. I've become too dependant on just asking questions here.



From the book I learned something new. The viscous drive is activated by air temperature coming through the radiator not the engine temp. Book says it should come on at 160° to 179° so it should work the same as with the 190° stat.



They mention the freewheel test so I'll go try that. I'm not going to do the whole thermometer test that they say to use.



I guess I still need to look into a seperate fan for the transmission cooler.



Garrett

 

[Morepower]

Good Idea putting on a separte fan up front with a manual switch. I have an aftermarket BD trans cooler that kicks in at 180 but can not keep up with transmission heating towing in town with lots of red lights. It is only about 10" diameter. I think I will look into having one up front now also.

 

[Peter Campbell]

It makes sense. If the trans cooler is on the cold water side of the radiator, and the fan does not go into service when the thermostat opens it follows that the trans cooler sees hotter water. To transfer heat you need a difference in temperature. So the air leaving the radiator at 160 F with 180 F water in the radiator is also reasonable. I see this with the horton fan clutch. Have westach temperature on the oil dipstick, if it gets too hot I turn on the fan and drop the oil temperature- by dropping the water outlet temperature.

 

[juicedcummins]

Big White Beast,

I have noticed higher trans temps since the Horton was put in. Same result as a fan not engaging because of the lower t-stat.

For me I would rather have them a little warmer for the winter use because winter temps here are -30C to -40C depending on the winter.

On the highway mine will drop to 65F in the winter but will climb back to 170 or so when idling after being on the highway. [pan temp]