DIY: Automatic Transmission Fluid Change
 

Howdy,


As part of the process of installing an ATF cooler this week, I had to do an automatic transmission fluid change, and I noticed there wasn't any DIY guides on the forums for this yet, so figured I'd write one up.


Disclaimer: While I didn't think the process itself was all that bad after I'd done it once, it is one of those things where if you mess up the fluid leveling procedure it could cause serious damage to your transmission. So be aware, pay attention, and if in doubt take your car to a professional.



Tools Needed:

• A floor jack
• Four (4) jack stands
• 10mm, 12mm, 14mm, and 24mm sockets
• 5mm hex key or hex key socket
• A small piece of wire to make a jumper
• A fluid transfer pump
• An oil drain pan that can hold 8 quarts or more
• Crush washers for the drain and overfill plug, Subaru part number 17008AA000.
• O-Ring for the Fill plug (part number TBD)
• 7 US quarts of Toyota WS or approved full synthetic ATF. I used Redline D6 ATF

Reference Documentation:

• Attachment 169877

https://i.imgur.com/P1drtF1.jpg

https://i.imgur.com/yeLYnX0.jpg

https://i.imgur.com/7SBixxN.jpg

Steps:

1. Safely jack the car up on a flat horizontal surface and get all four wheels off the ground on jack stands
2. Remove the engine under tray (12mm and 10mm bolts)
3. Remove the transmission under tray (10mm bolts)
4. Prepare your oil drain pan and a ratchet with each 14mm and 24mm sockets and the 5mm hex key socket.
5. Ensure you can remove the 24mm refill plug by breaking it loose
6. Remove the drain plug to drain into the pan, don't lose the crush washer
7. Install and tighten the drain plug and crush washer
8. Remove the refill plug
9. Using the fluid transfer pump, add 2.1 US quarts of ATF (I added 2 quarts-ish, and then had one bottle I funneled the last bits I couldn't pump into and used it to get myself a .3 or so into the last go)
10. Install and tighten the refill plug, making sure to lightly lubricate the o-ring with ATF
11. Crank the engine, allow it to idle for a moment and then while keeping your foot on the brake slowly move from Park to Manual and back to Park, pausing for a moment at each one. Do this twice.
12. Shut the engine off, allow to cool for 2-3 minutes
13. Remove the drain plug to drain into the pan, don't lose the crush washer
14. Install and tighten the drain plug and crush washer
15. Remove the refill plug
16. Using the fluid transfer pump, add 2.1 US quarts of ATF
17. Install and tighten the refill plug
18. Crank the engine, allow it to idle for a moment and then while keeping your foot on the brake slowly move from Park to Manual and back to Park, pausing for a moment on each one.
19. Shut off the engine, allow to cool for 2-3 minutes
20. Remove the drain plug to drain into the pan, discard old crush washer
21. Install and tighten the drain plug with a new crush washer ensuring you lubricate the crush washer lightly with ATF
22. Remove the refill plug
23. Using the fluid transfer pump, add 2.1 US quarts of ATF + any dregs remaining from previous additions
24. Remove old o-ring from refill plug and install a new o-ring, lubricating lightly with fresh ATF
25. Install and tighten the refill plug
26. Insert a jumper between pins 4 (common ground) and pin 13 (TC) on your OBD2 port
27. Start the engine, your check engine light should be flashing to let you know you have the jumper connected
28. With your foot on the brake, slowly move from Park to Manual and back to Park, pausing for a moment on each one.
29. Then move the shifter to Drive and then quickly back and forth between Drive and Neutral (within 1.5 seconds) for at least 6 seconds. The car will be in fluid temperature detection mode when you see the up and down shift indicators illuminate together for 2 seconds and then turn off.
30. Shift the car back into Park and remove the jumper wire.
31. Leave the engine running.
32. You should see the shift indicator showing in Park. If the up arrow is showing your transmission is too hot and you need to wait for it to cool off and try again, if the down arrow is showing the transmission needs to warm up. If both arrows are showing then the temperature is within the correct range (108F-117F).
33. With both arrows showing and the engine idling, remove the overflow plug and drain into the pan.
34. If fluid doesn't come out, open the refill plug and add fluid until it drains from the overflow at a slow trickle, otherwise wait for fluid to drain until it drains at a slow trickle.
35. Reinstall the overflow plug with a new o-ring lightly coated in fresh ATF and tighten.
36. Shut the engine off
37. Torque your Refill plug to 29 ft-lbs
38. Torque your Overflow plug to 15 ft-lbs
39. Torque your Drain plug to 15 ft-lbs
40. Wipe down all surfaces
41. Start your engine and move your shifter slowly from Park to Manual and back to Park.
42. With a flashlight check all plugs and surfaces for leaks.
43. Shut your engine off, reinstall the under trays, and safely bring your car off jack stands and back to the ground.

That's it, you're done. In simplified form, you do 3 drain/refills, then do a fluid leveling procedure. The reason you do this is because most of the fluid in the transmission is not in the transmission pan but is actually held in the torque converter and the valve body. By shifting after each fill procedure you're forcing the fluid to move around in the transmission and exchange.


I hope this helps someone!

Holy crap well done, a pretty thorough and much better explanation than the service manual I followed for mine :lol:


A little suggestion it might help to lower the size of the photos and put them below or with the step they correspond to. Also nice job using imgur to host the images, I don't see alot of people do that on the forum for some reason people use photobucket or others.

Also I wouldn't suggest an exact amount for every fill and run cycle, I filled it till it dripped out the refill plug.

Thanks! I resized the images and ran them through ImageOptim and re-uploaded, so maybe they'll load much faster and be more manageable when zoomed in now.


For the refills, I actually "cheated" and did 2 US quarts on the first one, 2 on the second, and 3 on the third go around + the dregs, then leveled it. I had bought 7 quarts, I used 7 quarts :) I never had anything drip out of the refill plug.

Are all these steps in the bottom for levelling the fluid done with the engine running? like when both the shift lamps are showing, do i open the overflow plug with the engine running or turned off?

With the engine running, if it trickles out at the right temp your good if nothing comes out its low if too much comes out its over fill,

Everything is done with the engine running in these steps. You need the engine running to go up to temp and it requires the engine running to shift the transmission during the steps to circulate fluids as well.

wow I can't believe we didn't have a proper DIY thread until 2018 !
thank you very much for your post, it makes things a lot easier.

the below resume helps understand the whole process:
drain/overfill, engine on, Park to M & back
drain/overfill, engine on, Park to M & back
drain/overfill, bring oil to "proper" temp, & drain through overflow until it's thin as a thread.
tighten everything to spec.

So could you just change out the fluid once.

Let it run until the next oil change and change it out again with the next oil change or two.

So I went to a local subaru specialized shop to get my automatic transmission oil changed.

They drained the ATF, put new ATF, shifted it and made sure fluids was the correct level. They also changed the o rings and ended up only using 3 quarts.

They told me they never done it any other way, not even putting a jumper wire to make sure the fluid was the right temperature.
Should I be worried and do it within like 5k miles or 30k miles or should I just wait until the next internal, which is 60k miles, to change it again?

Can you do a video please?

It’s as simple as @86Kenshins post a few posts up. Only missing step is trans temp. You’ll either need to do the extra steps to get the temp lights. Or just go buy a scangauge and you can always see trans temp. I got AFR, oil, coolant, trans temp always on mine it’s great. And makes the trans fluid change procedure a breeze.

Does a OBDLink read trans temp?

So on the third drain/fill from the plug WS from above pic...get the oil to temp then undo the overflow bung till nothing comes out?

How many L do you use?

Yes, that is how it gets the reading in the first place, you can hook up with a scangauge to get the precise temp. Instead of a temp “range” using the temp light procedure.

Approximately 2L or 2.1quarts each drain/fill, i would just get 7L/Q to be safe.

3 drain/fill. After each fill need to turn car on idle for a sec and slowly move from P to D and back stopping for at least 10seconds at each point, do this twice per each drain/fill so 6 times total. keep foot on brake entire time if still on stands. This helps circulate the new fluid.

On the final drain/fill overfill it, (id just use whatever you have remaining maybe save .2L to be safe assuming you got 7L to start). Do the P-M idle procedure above. Then let the car sit to cool down assuming its over 108F by now. Then with the car running in idle as soon as it hits 108F pull the overflow plug and cap it when the stream is a very thin thread but not completely stopped. (had wife sit in car to tell me the second it hit 108f as you can’t go over 117F so need to be quick especially if its way overfilled, might need to cap plug cooldown and try again before its done draining to “spec”).

The final leveling should be done on as level of ground as possible most garages should be fine assuming you jack both ends up evenly.

Summary

Engine off - Drain/fill 2L - idle P-M and back twice stop 10 seconds each point
Engine off - Drain/fill 2L - idle P-M and back twice stop 10 seconds each point
Engine off - Drain/fill 2.5L - idle P-M and back twice stop 10 seconds each point
Engine off - cool down trans temp to below 108F.
Idle warming up trans temp to above 108F but below 117F - pull overflow plug and replug when stream is a very thin thread but not completely stopped.

Anyone know of a scan tool that can read transmission temps.
Got a OBDLink MX+, it works in default mode but cant read transmission temp.
I tell it its a scion frs and download the enhanced add-on, it seems to works and finds a shitload of modules but then won't show them.
Chose Network A

There is no such thing a toyota 86 listed in enhanced add on.