Why is the AT dipstick always reading "cold"

[Baja Runner]

Well, I probably always overlooked this, but I am wondering why my AT dipstick always reads in the cold range. The dipstick itself is luke warm at most, and same with the fluid. The tranny cooler is hot to the touch though.

Sooo... whats going on?

This is after driving city/highway to my house, going through all the shift positions for a few seconds, leaving the truck running, and checking the level.

 

[the great him]

cause you low on tranny fluid

 

[Gerdo]

There are two "full" fill levels. One when the trans in cold and one when hot. Fill it to the top of the hot mark after driving. After driving, the fluid will be inside the torque converter. I always check when hot, I feel that you get a better reading.

 

[zcruiser]

Gotta make sure it's rammed in all the way.

Our tranny dipsticks suck balls.

 

[Baja Runner]

Well, I'm aware there is a hot and a cold, I am aware it needs to be all the way down, but like I am asking:

Why would the fluid on the dipstick be cold to the touch after driving?! Our AT's operate at like 160 to 210F ,... the fluid on the dipstick should be that temperature after driving. The cooler is hot to the touch as it should be, but the dip stick and fluid on the dipstick is not!!?!?

 

[zcruiser]

Well, I'm aware there is a hot and a cold, I am aware it needs to be all the way down, but like I am asking:

Why would the fluid on the dipstick be cold to the touch after driving?! Our AT's operate at like 160 to 210F ,... the fluid on the dipstick should be that temperature after driving. The cooler is hot to the touch as it should be, but the dip stick and fluid on the dipstick is not!!?!?

My guess is that heat is not being transferred to the dipstick and that there's not enough volume of fluid on the dipstick to hold the heat enough to "feel" hot when you take it out. And, it's a pretty long stick, made of thin material, that dissipates the heat pretty quickly.

That's all I got.

 

[Elton H]

Gotta make sure it's rammed in all the way.

Our tranny dipsticks suck balls.

:lmao:

 

[quicksilvr]

Well, I'm aware there is a hot and a cold, I am aware it needs to be all the way down, but like I am asking:

Why would the fluid on the dipstick be cold to the touch after driving?! Our AT's operate at like 160 to 210F ,... the fluid on the dipstick should be that temperature after driving. The cooler is hot to the touch as it should be, but the dip stick and fluid on the dipstick is not!!?!?

Also....you could just not be getting it actually warmed up. I watch my trans temp every day on my SGII, and unless you drive for at least 20 minutes, and do 5-7 full stop and start's with decent acceleration, the trans won't really warm up.



If you just accelerate a couple times, and then cruise on the highway, the trans temp is probably only like 110-120.

 

[nacho]

That explains why my tranny gauge always stays below 120 every since I bypassed the factory AT cooler and installed the B&M 70268 cooler. I also
live on the coast of Or. where it hasn't gotten over 70 degrees since I did
the install. It's good to know my tranny is running only warm and never gets
that hot anymore.

The tranny dipsticks on these 3rd gens are hell to get back in once you pull
it all the way out to read it. At least mine and 2 others I looked at were like
that too.

One thing I would like to know.....what is the best tranny fluid to use in
these 3rd gens? I heard that the higher the #..example dex 11V is better
than dex 1V. wtf?

 

[the great him]

Also....you could just not be getting it actually warmed up. I watch my trans temp every day on my SGII, and unless you drive for at least 20 minutes, and do 5-7 full stop and start's with decent acceleration, the trans won't really warm up.



If you just accelerate a couple times, and then cruise on the highway, the trans temp is probably only like 110-120.

yeah it takes a bit for our trannys to warm up

That explains why my tranny gauge always stays below 120 every since I bypassed the factory AT cooler and installed the B&M 70268 cooler. I also
live on the coast of Or. where it hasn't gotten over 70 degrees since I did
the install. It's good to know my tranny is running only warm and never gets
that hot anymore.

One thing I would like to know.....what is the best tranny fluid to use in
these 3rd gens? I heard that the higher the #..example dex 11V is better
than dex 1V. wtf?

your gauge is wrong my friend, i have dual coolers on my tranny, one is the larger B&M 70264, and the other is an even larger Perma-Cool with an electric fan on a thermo switch, and i still see temps over 200. most of the time around town im around 160-190 and on the freeway im just at 150, its not till i come to a good long hill or steep grade do i see over 200, but i never have seen my temps below 140 after it warms up, even if i just let it sit an idle at night(well after sundown) for 30min or so it will only drop to about 145. so either your gauge is wrong or you dont drive it long enough to warm up. and as far as the fluid goes, use dex IV, i believe thats what these trannys like(double check the dip stick) these Aisin trannys are picky

 

[nacho]

Something seems wrong if you're still getting around 200 degrees and you
are using 2 tranny coolers. That just seems way too hot for normal driving
conditions. It's more what I would expect with just the stock set-up only.

Are both of your coolers dedicated to only your tranny, or do they also run
through your lower tranny and radiator too? To avoid the pink milkshake, it
is advised to dedicate your tranny cooler(s) to only your tranny. You more
than likely already know this.

Did you put the in and out lines UP, SIDE WAYS, or DOWN? My research
shows that only side ways or up are recommended. If you run the intake line
into the side top of your cooler, gravity can just pull the fluid straight down
and it won't get a chance to fill up the rest of the cooler and therefore help
to make sure it's completely full of AT fluid with no air pockets. This is what
I read. It's best to have the AT fluid come in from the bottom side and out of the top side and back to your tranny. With the in and out lines facing up, it doesn't matter for obvious reasons. I ran mine straight up for convienence.

I installed a manual 2" SunPro CP8 217 tranny fluid temp gauge with the
sensor going into a tee right before it goes into the B&M cooler. From there
it routes back to the tranny where it heats back up again. I had to use 12ft.
of 3/8" tranny line to complete my set-up. Maybe all the extra length of
line helps cool the fluid faster? All I know is it's hard for me to get the temp
up over 135 with my set-up. The B&M cooler is flush against the condenser
and mounted up higher where it gets direct wind through the grill with no
real obstructions. If you mount them too low, the bumper will block much of
the air flow I noticed.

Here's a diagram of how I hooked up my manual AT fluid temp sensor.

As a side note, when I first bought the manual gauge, I put the sensor end
into a pot of boiling water. The temp went right to 212 degrees and stopped.

http://www.toyota-4runner.org/3rd-gen-t4rs/69257-mechanical-transmission-temp-gauge-install.html

 

[the great him]

then your not driving it long enough... im armored and have E rated 285s on 17" wheels ect. im pushing around a lot of extra weight, its all being transferred to the tranny as im still stock 4:10 geared. i only see the 200+ on steep grades or long climbs(i should have also stated that my AC has to be on as well, to see those temps). i generally drive my truck for at least 40min before it gets shut down. both of my coolers are side by side, and side ported, they are up flush with the AC condenser. no i have by passed the radiator all together.

 

[Gerdo]

Why would the fluid on the dipstick be cold to the touch after driving?!
... but the dip stick and fluid on the dipstick is not!!?!?

Try laying the "Hot" dipstick on some more sensitive skin like the back of your hand.
It should be hot. I've seen dipsticks come out smoking hot (probably due to the proximity to the exhaust). I don't have an auto in my 4runner so I can't try mine. I wouldn't be concerned.

 

[Baja Runner]

OK so I did a little test:

This morning, I turned my car on for the fist time, and let it idle through all the gears for a few seconds. Then I left it running and in park and checked the dipstick. It was on the high level of "COLD"... Ok thats good right? ... Right!

Well I just got back from a city drive and came back, left the car running in park and checked: Still in the same place as it was this morning, but the dip stick was warm and the fluid was warm as well...

It doesn't make much sense to me because the AT cooler is hot to the touch.

Meh... I am not having any probelms, its just trying to figure out whats going on!

 

[the great him]

well part of the issue could be most of your heat come from the torque converter, pump and valve body, not the pan itself, all that stuff heats the fluid, then it passes through the cooler, thus making it hot to the touch. its cooled and it returns to the pan where it waits to be picked up by the pump and circulated through the system again. the pan is where your dip stick reads from. if you have a cooler, especially an aftermarket cooler and your fluid is only warm, not hot the cooler is doing its job. you might want to add a half a qt more fluid(to compensate for the added capacity of the added lines and cooler if you havent already done so)

 

[Baja Runner]

Well, the cooler is hot to the touch, and the inlet and outlet hoses are hot as well. I'd guess the outlet line, coming out of the cooler is about 20*F cooler than the inlet line, but still HOT.

The pan seems to be just cool/luke warm. Maybe the AT fluid has a very low heat capacity or something? I should look that up.

I would just assume that the dipstick has 2 readings (hot and cold) for when the tranny is warmed up after driving to compensate for fluid expansion.

Nevermind, I guess I'll just let it go...

Another thing that pisses me off about this 4runner is that the oil dipstick doesn't read correctly as well. With 5.5 quarts after a new oil change, it still reads its 1 qt low.