My ATF never gets Hot?

[Rhymingmechanic]

Check the pan temp with the infrared, too.

If it was mine, I would add 4 ounces at a time until the level at least reaches the bottom of the "hot" range after a long drive.

 

[Whimsey]

Why not check it when it's cold and if need be add to bring up to the cold mark level. Then check it hot afterwards and see where it is on the dip stick. I would think that a correct cold level would give you a correct hot level, when "hot".

Whimsey

 

[Gebo]

Whimsy, that’s my issue. It doesn’t. It won’t raise to the hot level

 

[LeakySeals]

Originally Posted By: Gebo
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.


If I read this right, you're referencing dipstick markings to determine whether your transmission is hot. Thats not what the refrence marks are for. They tell you the level of the transmission fluid when its "cold" (contracted, recently started) or "hot" (expanded, after towing, or an hour on the highway on a hot summer day). So from what you described, its slightly low. Maybe 1/2 qt. get it hot again and add some fluid until you are just below the "hot" line. Or just leave it alone. Better a little low than too high..

 

[Gebo]

LeakySeals, my ATF is at the upper cold mark when I check the level immediately after checking when cold. After driving for 2 hours on interstate pulling a trailer I check it and it now just reads about 1/2 inch above the upper cold mark. No where near the hot range on the dip stick. I’m assuming the ATF won’t get any hotter than after 2 hours running on interstate pulling a trailer.

My question was do I leave my level alone or add more fluid to get it at least to the bottom hot mark.

 

[kschachn]

In the owner's manual for both of my cars that have automatics (and a dipstick) it says that the cold mark is only to be used as a minimum to prevent damage. If it is below that mark the vehicle should not be operated. So if the car has not been operated or if I am doing a drain and refill, I fill it to the cold mark before I warm up the transmission and check it hot.

The upper mark is the maximum level when the vehicle has been operated and it should not be filled above that level. The space in between is acceptable for operation when checked warm per the specific instructions in the manual.

 

[Whimsey]

Originally Posted By: Gebo
LeakySeals, my ATF is at the upper cold mark when I check the level immediately after checking when cold. After driving for 2 hours on interstate pulling a trailer I check it and it now just reads about 1/2 inch above the upper cold mark. No where near the hot range on the dip stick. I’m assuming the ATF won’t get any hotter than after 2 hours running on interstate pulling a trailer.

My question was do I leave my level alone or add more fluid to get it at least to the bottom hot mark.


Overfill or under fill is not a good idea with AT's. With your cold level fluid seeming to be in the proper range for cold fluid how does your transmission shift when cold and running after usage, such as towing? If it shifts fine then I'd use the cold fill level to measure the correct AT fluid level and not worry. The cold level will be more consistent than varying levels of the definition of hot. Of course this presumes you do check the ATF when it's "cold".

Whimsey

 

[Linctex]

Originally Posted By: Gebo
Ok. It amazes me I can pull a trailer 5 hrs on the interstate and it only gets warm to the touch.


That is the BEAUTY of modern lock-up torque converters!

You wouldn't see temps that cool with the converter unlocked.
That is where all the heat comes from - not the gears.

 

[MolaKule]

Originally Posted By: Gebo
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...



Take it to Phoenix this summer and hook up a scanner and watch the ATF temp.