4th gen Tacoma transmission fluid change DIY

The UA80F transmission uses an internal fill-level tube (a "standpipe") instead of a traditional drain plug.

2025 Tacoma UA80F Transmission Fluid Drain & Fill Guide

Transmission: UA80F (8-speed automatic)
Fluid: Toyota WS ATF (World Standard)
Capacity (Drain & Fill): Remove overflow plug and internal standpipe (level tube)


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Tools & Materials

4–5 quarts Toyota WS ATF

Fluid pump (with hose for side fill)

5mm Allen wrench (for inner level tube) and outer plug

24mm socket (fill plug)


My process

1. Warm the Transmission

Start engine and let it idle.

2. Level the Vehicle

3. Drain Old Fluid

Locate the transmission drain/overflow plug (5 mm hex) on the bottom of the pan.

Place a drain pan beneath it and remove the overflow plug.

You'll see a slow dribble — this is from the internal standpipe.

Insert a 5mm Allen wrench into the center of the opening and remove the standpipe (aka "fill level tube").

Fluid will now drain fully

4. Reinstall the Standpipe

Once fluid stops draining, reinstall the internal level tube (hand-tight, don’t overtighten).

5. Fill with New Fluid

Locate and remove the fill plug (24mm hex) on the upper driver’s side of the transmission case.

Using a fluid pump, fill Toyota WS ATF until it begins to dribble out the overflow port.

Wait for it to slow to a light stream or drip, indicating the pan is full to the level tube.

Temporarily install the overflow plug hand tight only.

6. Start Engine & Check Level at Temp

Start the engine, leave vehicle in Park, and let it idle. Put it in all the gears.

Remove the overflow plug (again).

If fluid dribbles out, the level is correct.

If no fluid comes out, add more ATF thr









4ough the fill port until it dribbles.

Replace and torque bolts

Very thorough walkthrough, thank you for this. May I ask at how many miles you performed this trans drain and fill?

I over heated my transmission when I was off roading. I was only at 5000 miles but decided to change it just in case. The fluid was a bit used but not terrible. I probably could have gone longer on it but once I was in it, I just completed it.

559Taco said:

The UA80F transmission uses an internal fill-level tube (a "standpipe") instead of a traditional drain plug.

2025 Tacoma UA80F Transmission Fluid Drain & Fill Guide

Transmission: UA80F (8-speed automatic)
Fluid: Toyota WS ATF (World Standard)
Capacity (Drain & Fill): Remove overflow plug and internal standpipe (level tube)


---

Tools & Materials

4–5 quarts Toyota WS ATF

Fluid pump (with hose for side fill)

5mm Allen wrench (for inner level tube) and outer plug

24mm socket (fill plug)


My process

1. Warm the Transmission

Start engine and let it idle.

2. Level the Vehicle

3. Drain Old Fluid

Locate the transmission drain/overflow plug (5 mm hex) on the bottom of the pan.

Place a drain pan beneath it and remove the overflow plug.

You'll see a slow dribble — this is from the internal standpipe.

Insert a 5mm Allen wrench into the center of the opening and remove the standpipe (aka "fill level tube").

Fluid will now drain fully

4. Reinstall the Standpipe

Once fluid stops draining, reinstall the internal level tube (hand-tight, don’t overtighten).

5. Fill with New Fluid

Locate and remove the fill plug (24mm hex) on the upper driver’s side of the transmission case.

Using a fluid pump, fill Toyota WS ATF until it begins to dribble out the overflow port.

Wait for it to slow to a light stream or drip, indicating the pan is full to the level tube.

Temporarily install the overflow plug hand tight only.

6. Start Engine & Check Level at Temp

Start the engine, leave vehicle in Park, and let it idle. Put it in all the gears.

Remove the overflow plug (again).

If fluid dribbles out, the level is correct.

If no fluid comes out, add more ATF thr
View attachment 36099

View attachment 36103 View attachment 36104 4ough the fill port until it dribbles.

Replace and torque bolts

Click to expand...

Probably a good idea. Just curious if you read something to make you want to change it? Something to do with Toyotas previous tranny problems? Toyota considers the WS fluid in the UA80F transmission to be "lifetime" fill, meaning it's not designed for routine replacement.
Thanks.

https://www.tacoma4g.com/forum/attachments/rm100000002h30z-pdf.21885/?force-system-browser=1

To get the proper level, you must also set the transmission thermostat and put the system in fluid temp mode to get the temp window correct. Heres a link from the OEM service manual to fine tune your procedure.

jmho...but I would not touch it unless out of warranty...over heat or not...but when you like "wrenching" we tend to find reasons to do it...being a old head not my game any more

Hi, there is no such thing as a lifetime transmission fluid. His reasoning for changing his works for him.

glk21c said:

Hi, there is no such thing as a lifetime transmission fluid. His reasoning for changing his works for him.

Click to expand...

Works for me, too. Think that's a darned good reason and why I keep the thermostat's gauge on my dash display.

PullinDoubles said:

Probably a good idea. Just curious if you read something to make you want to change it? Something to do with Toyotas previous tranny problems? Toyota considers the WS fluid in the UA80F transmission to be "lifetime" fill, meaning it's not designed for routine replacement.
Thanks.

Click to expand...

This concept pops up often on reddits and forums, and the "lifetimes" were, from what i understand, tied to the warranty periods and life expectancy of when most people trade cars (100,000-150,000). And i believe it was for non-truck vehicles, camrys, etc.

The manuals for all Toyotas have and always have had service intervals for transmission fluids. I would never leave it in indefinitely and after about 50,000 miles, i drop and fill every couple oil changes. Ive done it for all my Tacomas.

https://www.agcoauto.com/content/news/p2_articleid/45

Someone sent this link on TW and it's honestly one of the better articles on how/why trans fluid is not a lifetime fluid. For anyone that goes offroad its probably more like a 20k mile fluid to be honest, which is what I'll do.

The site also has an article that lists the dangers of trans "flushes" vs the actual trans service process of drain and fill.

Aisin says every 12,000 miles which sounds pretty aggressive, but they also want to sell you trans fluid LOL

But I have a feeling they wrote this with the assumption that if you did 20,000km in 2 years you were doing a ton of short trips, city driving only, in which case I would agree with their recommendation.

PullinDoubles said:

Probably a good idea. Just curious if you read something to make you want to change it? Something to do with Toyotas previous tranny problems? Toyota considers the WS fluid in the UA80F transmission to be "lifetime" fill, meaning it's not designed for routine replacement.
Thanks.

Click to expand...

Mixture of 24 transmission issues and just being over concerned after the transmission overheated.

Nicely done, nice writeup. And good on you for being proactive about the fluid, even if some others might think it's unnecessary. The peace of mind is well worth it.