My ATF never gets Hot?

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Without mentioning any names, I have noticed my ATF NEVER gets hot. I pulled a lawnmower on a trailer for 2 hours on the interstate and my ATF was barely warm. I know that's good. BUT...

How do I determine proper fluid level? This vehicle has a dipstick so I can check it. Do I keep it between the "COLD" hashmarks or do I add up to the "HOT" hashmarks? I ain't making this up. As soon as I got back home from the haul, I kept 4Runner running, shifted through all the gears, pulled the dipstick out, wiped it off, reinserted and the reading is slightly above the upper "COLD" marks but no where near the "HOT" range.
 
Do you think it's not at the correct fill level? I'd fill it to the cold line when it's cold (around 65°F).
 
It sounds like you need to add a little ATF...unless I'm reading your post wrong?
You need to check your ATF temp.
 
Originally Posted By: Trav
What is the temp of the fluid?


Good question. OP-How did you determine the transmission fluid temperature? The fluid level changes with the temperature. I have a chart with temperatures and a special dipstick for both my Jeeps to determine the correct level based on temperature. As the fluid gets hotter the level moves higher. As long as the level corresponds with the temperature on the chart the level is correct. Without knowing the correct temperature of the ATF the level cannot be accurately set.
 
Originally Posted By: demarpaint
Without knowing the correct temperature of the ATF - the level cannot be accurately set.


Yes, you cannot put the cart before the horse.

Oh, BTW... as long as you are "somewhere around there" on your fluid level, you are fine.

Don't get obsessed about your oil level being ~4mm off (up or down) or something silly like that.
 
Originally Posted By: zorobabel
Are you determining the "hotness" of the ATF by the fluid level on the dipstick?


By how the fluid feels on my fingers while touching the dip stick
 
Originally Posted By: Trav
What is the temp of the fluid?


I was just going by feel and comparing it to how my water feels at 130 degrees coming out of my spigot at home. Maybe I should infrared it?
 
Originally Posted By: silveravant
What does your owner's manual say? The answer to many questions.


You aren't understanding my question. Owner's manual can't answer this question.
 
Originally Posted By: demarpaint
Originally Posted By: Trav
What is the temp of the fluid?


Good question. OP-How did you determine the transmission fluid temperature? The fluid level changes with the temperature. I have a chart with temperatures and a special dipstick for both my Jeeps to determine the correct level based on temperature. As the fluid gets hotter the level moves higher. As long as the level corresponds with the temperature on the chart the level is correct. Without knowing the correct temperature of the ATF the level cannot be accurately set.


I was just going by feel as compared to my house hot water at 130. The fluid feels barely warm. I have touched other hot dipsticks (be nice
grin.gif
) and the fluid was so hot it would burn my fingers. Maybe time for the infrared.
 
I installed a temp gauge out of curiosity on my car. If I'm on the highway with torque converter locked, my ATF will barely get up to 130F in the winter even when hauling a full load for nearly an hour, and that's with a coolant to ATF heat exchanger in the radiator end tank.

If you want to get it really warm, drive around town such that the torque converter is working harder, since that is where most of the heat is generated in an automatic.
 
Originally Posted By: Gebo
Originally Posted By: Trav
What is the temp of the fluid?


I was just going by feel and comparing it to how my water feels at 130 degrees coming out of my spigot at home. Maybe I should infrared it?


By barely warm feel, it's temperature reading is likely well below 120f, possibly even lower.
This is a typically 'normal ' operating temperature of a gear train system with adequately high KV@40*C I.e thick oil , with or without friction reducing Moly/boron solid lubricants and your transmission is in good hands, IMHO.
 
Originally Posted By: Gebo
Originally Posted By: demarpaint
Originally Posted By: Trav
What is the temp of the fluid?


Good question. OP-How did you determine the transmission fluid temperature? The fluid level changes with the temperature. I have a chart with temperatures and a special dipstick for both my Jeeps to determine the correct level based on temperature. As the fluid gets hotter the level moves higher. As long as the level corresponds with the temperature on the chart the level is correct. Without knowing the correct temperature of the ATF the level cannot be accurately set.


I was just going by feel as compared to my house hot water at 130. The fluid feels barely warm. I have touched other hot dipsticks (be nice
grin.gif
) and the fluid was so hot it would burn my fingers. Maybe time for the infrared.


A scan tool can provide that info if you have one otherwise a cheap VOM with temp probe will do. Unless your transmission has a thermostat it probably wont go much over 130 or so in winter.
 
So do i keep adding ATF to get the fluid level up to the “hot” mark on the dip stick aftter checking the level with 50 miles of driving?

I realize that cooler ATF operating temperatures are better. It appears that synthetic ATF’s run cooler than non synthetic ATF’s. This being the case, after filling my transmission up to the “cool” marks on the dipstick, my ATF expands very little on the dipstick. It only rises about 1/3 of the way towards the “hot” mark. The fluid level checks fine cold but never gets to the hot mark after drinving. If i add more to get it to the hot level when hot, it will probably be way over the cold level when cold. Am i making any sense at all?
 
Ok. It amazes me I can pull a trailer 5 hrs on the interstate and it only gets warm to the touch. I’m gonna infrared it today as I’m taking my Mom to her Dr. and it’s a 2 hr drive.
 
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