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43k miles on my 2014. Took mine to Toyota of Princeton. $189 for the transmission drain and refill. With the “raise the front end” trick I told them about they were able to get a total of 5 quarts out. It’s always funny when you teach the dealer something. Shifting might be slightly better but I was not expecting much of a difference considering the low mileage. Preventive maintenance 👍
Excellent, easy-to-read step by step. 2 questions, why pin open the AT thermostatic switch? I have the ATF thermal degradation monitor, but not Techstream, if I never reset it, does it matter?
Originally Posted by Acrad
EDITED for what I actually performed for service:
•••This post will more than likely be edited multiple times. Think of this as a draft
Feel free to comment…. Just trying to get my steps in-line before I do a simple drain and refill on the AT fluid. This one seems like it can be a little more complicated than other vehicles I have changed AT fluid on as this first I have dealt with for the overflow design on the level check. I understand some may want to do some full change out through the AT cooler lines and/or change the filter. I am not going to do either this go around.
If I knew absolutely certain my current factory fill was correct I would consider a drain and refill without all the other steps but since that is unknown I am gonna attempt factory check method.
- Vehicle placed on 4 ramps for more room to work underneath. Made sure vehicle was level and wheels were chocked
- Turned vehicle to power on without starting. Connected OBD Fusion make sure that I could get a reading on “AT Oil Temperature 1”. (Pan Temp)
- Turned vehicle power off.
- Placed appropriate container with measurement marks below drain plug. I want to see how much drains out.
- Cleaned off AT fill plug. Fill plug is located on the right rear side of transmission.
- Removed 24 mm fill plug / make sure rubber gasket does not get lost. Important to first remove fill plug.
- Cleaned off AT fluid overflow check valve
- Remove 5mm hex AT fluid overflow check valve. With engine off there is more fluid in the pan than when running. A measured amount in my later post came out. This is optional. One could just fully drain from the drain plug.
- Cleaned off AT drain plug
- Removed 14 mm AT drained plug and drain AT fluid into container
- Reinstalled 14 mm AT drain plug with a new crush washer / torque: 15 ft-lb
- Pinned open the AT thermostatic switch with a paper clip. A screwdriver to push in switch will be needed.
- Used an old oil contain to exactly measure how much came out. I then added 1/2 quart to this amount so I could ensure I got an accurate fill level later on.
- Refilled transmission with (drain amount + 0.5 quart) with new fluid.
- Tighten the AT refill plug with old o-ring on it. I will be replacing with a new o-ring once we are sure fluid level is accurate. I probably retightened to like 10 ft-lbs. I wouldn't go full torque spec in case you under-filled and have to remove fill plug again.
- Hand tighten AT overflow check valve with old crush washer (only if you optionally removed during drain)
- Start Vehicle and cycle through gears a few times with foot on the brake and go through all the gears for about 30 seconds.
- Return to park.
- Double checked to make sure I could connect and see temps with OBD Fusion. I was able to keep the phone down with me under car so I could watch temps.
- Make sure you have your drain container down there again
- When temperature hit 115 degrees Fahrenheit I removed the AT overflow check valve and drained excess fluid until a slow trickle of fluid started coming out of AT check valve. Be careful not get burned with hot fluid or the nearby exhaust. I then reinstalled the overflow check valve bolt. I would be prepared to put a new crush washer on the bolt right after removal. Check valve torque 15 ft-lb
- You should now have the factory spec correct AT level
- Turn off vehicle
- Replace O-ring on hand tightened fill plug and torque to: 29 ft-lb
- Remove pin from AT thermostatic switch
- Go for a test drive to ensure shifting is correct.
- Check for any leaks when you get back from drive.
I am going follow acrad's step by step guide and do drain and fill this weekend. A few more questions:
1. I bought 6 qts of WS, and plan to do 2x of drain and fill, so each time I drain about 3 qtr and put in 3 qtr. Does this look right to you guys? I recall some folks drain more than 3 qts.
2. I have an OBD2 fusion, so I can check ATF pan temp (temp1) for it to get to 105F to 115F range, and then do the overflow drain. My question is: shall I turn off the car once the temperature reaches target, I very sedom get under a running car (even in neutral). Just want to make sure I feel comfortable about the process.
3. Is it better if I shall drive around 20 min between 1st drain & fill and 2nd one? Or I can simply shift through P,R,N,D for a few minute to mix the old and new ATF? Mine has 74K and this is the first time, so I figure ATF is dirty.
renau001: A few thoughts on the thermostat pin a few post back at 401 forward. https://www.clublexus.com/forums/gx-...l#post10968489
It isn't a requirement to reset that monitor but statistics for that parameter will simply stay at the max of 65536.
I would be curious if any dealers who perform multiple drain and refills reset the Thermal Degradation Estimate. Still a lot of speculation about the parameter.
william489: I had around a 2.7 quart drain but also had drains near 3.5 quarts. In my own experience I would simply put 4 quarts back in and drain the excess out. I figured it helped getting more clean fluid during the change and no chance of an [size=13px]under-fill[/size] either. Lavrishevo did mention the technique where lifting the front up even more during the drain can net additional fluid. My drain measurements are while vehicle is level. I'd probably count on having 4 quarts just in case your drains are over 3 quarts.. You do need the engine running to perform the drain and level check. When engine is off more fluid drains back into the pan and wouldn't give you an accurate level. You would end up draining too much out. IMO: You should be fine 20 minutes in between.
Thank you Acrad. You mean 20 min short drive in between drain & fill, or leaving car running for 20 min (at the same time shifting thru PRND a few more times) while the car is still on the ramp?
I never drove mine, run it through the gears a few times and you're good. You'll want to give it the 20 minutes to cool down a bit to get back under there.
Speaking of which, I need to order some more fluid and do this again...
https://www.tacomaworld.com/threads/...cu.535949/OBD2 Mode and PID: 22162B
Long name: ATF Thermal Degradation Estimate
Short name: ATF Degrad
Min value: 0
Max value: 65535
Scale: x1
Unit: –
Equation: A*256+B
OBD Header: 701
Diag. Start Comm: 1001
I am not an engineer but maybe some thought on question
Is there a way to reset this value if you were to change the fluid? Does it matter?
I assume they are using the Arrhenius equation for calculating the rate of change in the fluid. In general, for every 10°C hotter the fluid is, it will double the rate of reaction/degradation. So if the fluid is at 90°C normally, but hits 110°C towing a grade, your fluid is degrading 4x faster while towing than it was while not. I have seen close to 120°C towing prior to installing a larger air cooler and that would result in the fluid degrading 8x faster.
renau001: A few thoughts on the thermostat pin a few post back at 401 forward. https://www.clublexus.com/forums/gx-...l#post10968489
It isn't a requirement to reset that monitor but statistics for that parameter will simply stay at the max of 65536.
I would be curious if any dealers who perform multiple drain and refills reset the Thermal Degradation Estimate. Still a lot of speculation about the parameter.
william489: I had around a 2.7 quart drain but also had drains near 3.5 quarts. In my own experience I would simply put 4 quarts back in and drain the excess out. I figured it helped getting more clean fluid during the change and no chance of an [size=13px]under-fill[/size] either. Lavrishevo did mention the technique where lifting the front up even more during the drain can net additional fluid. My drain measurements are while vehicle is level. I'd probably count on having 4 quarts just in case your drains are over 3 quarts.. You do need the engine running to perform the drain and level check. When engine is off more fluid drains back into the pan and wouldn't give you an accurate level. You would end up draining too much out. IMO: You should be fine 20 minutes in between.
Thanks, sorry I read through a lot of the thread but missed that. Not sure if I have a OEM trans cooler, I do have a tow package installed at port, so I would hope so.
I’m doing a drain and refill every 36k on the SC and GX as Aisin recommends. Don’t forget the raise the raise the front end trick to get 5 quarts out. No need to drop the pan.
Thanks, sorry I read through a lot of the thread but missed that. Not sure if I have a OEM trans cooler, I do have a tow package installed at port, so I would hope so.
OEM tranny air cooler is part of the offroad package, not the tow package.
I’m doing a drain and refill every 36k on the SC and GX as Aisin recommends. Don’t forget the raise the raise the front end trick to get 5 quarts out. No need to drop the pan.
Correct me if my assumption is wrong, but I figured it’d be like doing the change in my 2011 5.7 Tundra. The process as I remember was
1)drain the pan with drain plug (record amount)
2)run a tube and funnel through the hood opening into the atf pan fill port
3)refill pan with amount drained in new ATF
4)disconnect cooler line into a bucket and crank car
5) add qts as you drain into a bucket with qts marked
6) get atf up to the right temp and open level bolt in ATF pan to get the correct level.
anyone do it that way? It’s a full drain and fill and not that difficult.
I have seen multiple methods mentioned and I don’t see any harm personally with the method you mentioned but this is not what Aisin recommends. I can’t speak to why but it’s not necessary to get all the fluid out at the same time. You are not gaining anything. Some argue it can be more of a shock to the system to replace all the fluid at once. I think this is particularly true for older transmissions that were not regularly serviced. Maybe there are other reasons as well. More people have reported issues with full fluid exchanges and flushes vs slowly introducing new fluid. The drain and refill has been consistently the safest method.
01-09-21, 11:53 AM
