How important is waiting 3 minutes before checking transmission fluid

[jalikaria24]

Hey guys i have a gm 4l60e in my truck and the owners manual says to drive around and get the transmission fluid hot. Then it says find a flat surface, shift thru every gear and wait 3 seconds. And then put it in park and wait 3 minutes before checking fluid while engine is still running.

What is the importance of the 3 minutes?
Is it just for oil to settle down that was flowing everywhere or is it just for it to cool down a smudge?


Thx

 

[zrxkawboy]

IME, if you check it right away, the reading will not be "clean" on the dipstick. I think the 3 minutes gives the fluid time to drain out of the dipstick tube and (like you mentioned) settle a bit.

 

[demarpaint]

At that point the fluid level has stabilized in the pan, as a result you will get an accurate reading. Experiment for yourself and you'll see why they tell you to wait.

 

[Sayjac]

I'm not familiar with topic vehicle or instructions, but I'd say in their testing the 3 min delay gives the most accurate level reading. Other than waiting and timing 3 minutes doesn't seem like much of an ask.

In Hondas case, it's get to operating temp, (fan engaged mentioned as indication), shut down. Wait 60 secs, but no more than 90 secs. The 30 sec window seems kinda goofy, but I follow it for level check anyway.

 

[bachman]

Good job following the instructions. Many vehicles I've owned have variations of how to check that illustrating the importance of knowing to follow the steps as indicated.
I've been in the same boat at times just curious about something like that even though 3 minutes wait is no big deal and easy to accommodate.


The easy thing is just pull 2 or 3 test examples waiting 3 minutes and 2 or 3 Not waiting 3 minutes. There is your answer. Coloration or tint differences ? Level differences ?
Report back !!

 

[Kira]

I have the same thing with different numbers.
1) Get it to temperature
2) With the engine still running, stop on level ground, foot on brake and go through the gears P to L and back to P, stopping 3 seconds at each detent.
3) Still with a running engine, go out and check the level WITHIN 20 SECONDS.

I think it's so fluid in the relaxed circuits can drain back JUST SO MUCH.
In other words, I think they've measured how much fluid clings to internal parts.
"I think therefore I don't know". Goethe, right?

 

[MolaKule]

Originally Posted by Kira
I have the same thing with different numbers.
1) Get it to temperature
2) With the engine still running, stop on level ground, foot on brake and go through the gears P to L and back to P, stopping 3 seconds at each detent.
3) Still with a running engine, go out and check the level WITHIN 20 SECONDS.


I believe that is the correct way to check fluids in most ATF's.

I would only add to take the average of three readings or so as others have mentioned as well.

 

[Pelican]

Originally Posted by apollo18
Hey guys i have a gm 4l60e in my truck and the owners manual says to drive around and get the transmission fluid hot. Then it says find a flat surface, shift thru every gear and wait 3 seconds. And then put it in park and wait 3 minutes before checking fluid while engine is still running. What is the importance of the 3 minutes?
Is it just for oil to settle down that was flowing everywhere or is it just for it to cool down a smudge? Thx


The waiting is for 3 seconds in each gear up & down the range and then put it in park and wait for 3 min (I'd wait 5min) before checking.

 

[1978elcamino]

Instead of waiting you can activate the linelock for 5 seconds at WOT, that will heat up the fluid real quick.

 

[Imp4]

Originally Posted by apollo18
Hey guys i have a gm 4l60e in my truck and the owners manual says to drive around and get the transmission fluid hot. Then it says find a flat surface, shift thru every gear and wait 3 seconds. And then put it in park and wait 3 minutes before checking fluid while engine is still running.

What is the importance of the 3 minutes?
Is it just for oil to settle down that was flowing everywhere or is it just for it to cool down a smudge?


Thx

If the checking sequence is this specific then it is important enough that you should exercise a level of patience appropriate to verify the level in a manner conducive to the designer's intent.
The three minute wait period is almost certainly designed to allow the fluid level to reach a stasis that results in an accurate measurement.

What else were you going to do during those three minutes anyway?

 

[jalikaria24]

Prepare your vehicle as follows:
Park your vehicle on a level place. Keep the engine running. With the parking brake applied, place the shift lever in PARK (P).
With your foot on the brake pedal, move the shift lever through each gear range, pausing for about three seconds in each range. Then, position the shift lever in PARK (P).
Let the engine run at idle for three minutes or more.



this is what my owners manual said, does that mean i go P R N D 3 2 1 and then 1 2 3 D N R P waiting 3 seconds in each gear positon?

because what i have been doing is flat surface, park, and then down to 1st gear with waiting 3 seconds in each position and then straight up to P again but now it seems like its a good idea to do 3 second wait down and up

thx!

 

[jalikaria24]

yesterday i went to check my fluid got it as hot as i could about 150f and then i found flat surface, did the 3 second wait, and waited 30 seconds to pop hood etc and then when i checked the fluid it looked low so i panicked. i checked a couple times and it was only in the cold area. so i drove somewhere else and i found a flat surface and did everything again, but i guess i took longer to check the fluid or maybe it settled down more since i was driving slow in a parking lot and kept stopping and then when i chekced there, the first dipstick pull was showing fluid in the hot section. so i was confused and did it 3 more times and noticed it kept getting a little higher and higher each time. so glad i didnt have to add fluid. because i was totally ready to add fluid. i will try again in the next couple days and sit in my vehicle for 3 minutes before checking. i am veyr impatient so usually i just go out and check 3-4 times which takes me 2 mins

thx

 

[kschachn]

If you followed the manufacturer's instructions properly and it showed low, then it was low.

On my automatic transmission vehicles I can get any reading I want if I deviate from the required procedure, all the way from overfilled to empty.

 

[jalikaria24]

i keep checking every couple days and it seems like it keeps lowering my 1/4 quart. i parked in my garage one day when i was doing an oil change and nothing dripped out, i usually park outside and check underneath and there is nothing ever underneath. can there be that much air in the transmission? i did a pan drop, filter change, and cooler line exchange to do the fluid change and i heard that the cooler line exchnage introduces air which can cause the fluid to lower over time, but i have added fluid like 5 times over 2 weeks and it still keeps lowering. i checked the cooling line i disconnected and the ground underneath always looks clean.

any tips?

 

[AC1DD]

Originally Posted by apollo18
i keep checking every couple days and it seems like it keeps lowering my 1/4 quart. i parked in my garage one day when i was doing an oil change and nothing dripped out, i usually park outside and check underneath and there is nothing ever underneath. can there be that much air in the transmission? i did a pan drop, filter change, and cooler line exchange to do the fluid change and i heard that the cooler line exchnage introduces air which can cause the fluid to lower over time, but i have added fluid like 5 times over 2 weeks and it still keeps lowering. i checked the cooling line i disconnected and the ground underneath always looks clean.

any tips?


Wow that seems odd, it could be air but I doubt it. I wonder if you have a leak in a seal somewhere.

IMPORTANT if you have a transmission fluid cooler built into the car radiator CHECK THE COOLANT FOR CONTAMINATION!!!! It will look like a strawberry milkshake it coolant and trans fluid have mixed. It is possible that there has been a failure of the radiator that would allow the two fluids to mix. It is critical to find this out and if there is contamination you need to replace the radiator and check the trans fluid, however it seems like yours might only be migrating from trans to radiator..

Not sure this is your problem but sounds possible.

 

[kschachn]

Originally Posted by apollo18
i keep checking every couple days and it seems like it keeps lowering my 1/4 quart. i parked in my garage one day when i was doing an oil change and nothing dripped out, i usually park outside and check underneath and there is nothing ever underneath. can there be that much air in the transmission? i did a pan drop, filter change, and cooler line exchange to do the fluid change and i heard that the cooler line exchnage introduces air which can cause the fluid to lower over time, but i have added fluid like 5 times over 2 weeks and it still keeps lowering. i checked the cooling line i disconnected and the ground underneath always looks clean.

any tips?

Are you checking it in strict accordance with the instructions in your owner's manual? If not then you can't make any sort of comparison.

 

[jalikaria24]

Originally Posted by AC1DD
Originally Posted by apollo18
i keep checking every couple days and it seems like it keeps lowering my 1/4 quart. i parked in my garage one day when i was doing an oil change and nothing dripped out, i usually park outside and check underneath and there is nothing ever underneath. can there be that much air in the transmission? i did a pan drop, filter change, and cooler line exchange to do the fluid change and i heard that the cooler line exchnage introduces air which can cause the fluid to lower over time, but i have added fluid like 5 times over 2 weeks and it still keeps lowering. i checked the cooling line i disconnected and the ground underneath always looks clean.

any tips?


Wow that seems odd, it could be air but I doubt it. I wonder if you have a leak in a seal somewhere.

IMPORTANT if you have a transmission fluid cooler built into the car radiator CHECK THE COOLANT FOR CONTAMINATION!!!! It will look like a strawberry milkshake it coolant and trans fluid have mixed. It is possible that there has been a failure of the radiator that would allow the two fluids to mix. It is critical to find this out and if there is contamination you need to replace the radiator and check the trans fluid, however it seems like yours might only be migrating from trans to radiator..

Not sure this is your problem but sounds possible.



thanks for the reply! so i just take that radiator overflow tank cap off and check in there?

thx

 

[jalikaria24]

Originally Posted by kschachn
Originally Posted by apollo18
i keep checking every couple days and it seems like it keeps lowering my 1/4 quart. i parked in my garage one day when i was doing an oil change and nothing dripped out, i usually park outside and check underneath and there is nothing ever underneath. can there be that much air in the transmission? i did a pan drop, filter change, and cooler line exchange to do the fluid change and i heard that the cooler line exchnage introduces air which can cause the fluid to lower over time, but i have added fluid like 5 times over 2 weeks and it still keeps lowering. i checked the cooling line i disconnected and the ground underneath always looks clean.

any tips?

Are you checking it in strict accordance with the instructions in your owner's manual? If not then you can't make any sort of comparison.



yes i am! level surface, transmission hot enough after 20-30mins of driving, and waiting 3 mins before checking after going thru every gear selector and waitiing 3 seconds each gear