Transmission Temp Cool?

[Harleymotorcycle]

My rams transmission runs around 110-120f just driving and was wondering if this is normal ram 1500 2013 it was 30f when I was driving when I hauling it will get around 160-180f

 

[HEMIMANN]

Yes. Ambient temperature has a huge impact on transmission oil temperature. But the 160-180 is too high for reasonable oil life, that's why many of us got rid of the trans oil thermostat that provides miniscule fuel economy improvement for having to change transmission oil far more often.

 

[Harleymotorcycle]

Yes. Ambient temperature has a huge impact on transmission oil temperature. But the 160-180 is too high for reasonable oil life, that's why many of us got rid of the trans oil thermostat that provides miniscule fuel economy improvement for having to change transmission oil far more

So running around 110-120 for trans temp is alright though?

 

[HEMIMANN]

So running around 110-120 for trans temp is alright though?

Yes. Heat destroys oils and transmissions, not cold. As all long as the oil still flows.

Transmissions didn't have oil thermostats until US EPA increased CAFE mileage regulations made car makers doing dumb stuff like this looking for the nth percentage mileage increase

 

[kurek]

low 100's is typical for the RFE transmission. Nothing to worry about. It does mean that over the long term moisture can contaminate the fluid (not boil off) but if you're exchanging the fluid every ~60k miles like you should then it'll never be a problem.

 

[crash68]

@Harleymotorcycle if your truck has the 8spd transmission (has shift knob) the that temp is actually on the cool side. The transmission can run up and around 200°F without any problems. It's old school thinking that 180°F is too hot for transmission fluid, there's quite a few 8spds that have racked up 100's of thousands while being worked hard towing without any problems.

 

[HEMIMANN]

What is "too hot"?

Too hot in terms of oil oxidation life are bulk temperatures above 140 degrees F. That's not "old school thinking", its physics and properties of materials.

I posted elsewhere with links for each 20 degrees F above 140F, oil oxidation life is cut in half.

Without access to regular UOA sampling of trans oil, we're guessing how much more often oil needs changing. It's exponentially shorter with rising temperatures.
Further, instantaneous oil temp in torque converters and gears is much higher than sump oil temp.
Saying it's all fine is not accurate.

 

[crash68]

It's old school conventional transmission fluid and last time I checked the 8 spd doesn't use it. Modern synthetics laugh at the higher temperature and lubrication properties are better even after running the miles that conventional fluid would be changed at.

 

[HEMIMANN]

"Old school" transmission oils were highly refined, turbine quality oils, same as hydraulics oils. Modern synthetics, particularly Group III, are similar and oxidize exponentially at the same rates.

 

[Hookedup87]