Transmission fluid - what to use and how often?

I just changed the oil on my 2021 4WD Tundra. 59,000 miles. I'm thinking about changing transmission fluid in the next few months but was wondering how often does it really need changing? Most of my miles are in a rural area and I very rarely tow a trailer.

Also, is Toyota transmission fluid absolutely necessary or are there others out there that perform just as well?

 

I’m no pro - literally just did my first one 10 minutes ago. I believe Toyota recommends 60k for a drain and fill.

As for the fluid, from the sounds of it the overwhelming majority of people say put Toyota WS fluid back in. I tend to agree just on the basis that when you drain and fill you’re only getting a few quarts out and who knows how different brands play together when they are mixed. Hope this helps

 

WS ATF, drain and fill every 30k miles.

 

Toyota WS, Idemitsu TLS LV and AISIN work well. I'd opt for 30k fluid changes. If you have a cooler which would be advisable you can almost do a complete fluid change instead of a few quarts here and there.
Some have good luck with the global fluids which are based on dex 6.

 

x3

WS ATF and D & F every 30k

 

I do my own D&F every 30k-ish miles.

I installed the cooler early on.

I have used Valvoline Maxlife ATF from the get-go.

WS=WS

I'm at 125k miles.

 

Good advice here. Thanks to all. When you say "drain and fill", are you just talking about draining the fluid from the drain plug at the pan? Not removing pan, cleaning the magnet and filter and replacing pan with new gasket? My dealership wants $350 to "drain and fill" but they suck the oil out and drain it. Seems like a lot for not taking the pan off.

 

Ive done it 4 times now at 135k. Maxlife for all changes

 

Do you just drain what you can from the plug in the pan and replace that volume?

 

No. After draining, you refill with slightly more than what came out. There is a procedure that involves getting the fluid up to temp and opening the check plug and letting the extra come out until it’s just a dribble. Then it’s full. If it’s low, and you didn’t know it and just put the same amount that came out back in, it would be low after your D&F.

 

I'm at 74K and to my knowledge mine has never been changed. I am the second owner. I am wanting to do it but nervous. I am not nervous about doing the work. I have just always heard if you change it after a certain amount of mileage, I may be doing more harm than good. I am open to opinions on that.

 

Drain and fill is “safe”

trans flush is not “safe”



if you can change oil. You can d&f a Toyota trans. It’s easier.

 

this needs to be repeated in every d&f thread



it sounds complicated

it’s not

I can do it

 

Thank you! I have never been a fan of a trans flush no matter how many miles. The fluid still looks good, But I would like to start changing regularly regardless. Thank you for the info!

 

And don’t clutch your pearls over the correct “temp”. When you check it

EVERY time I’ve done mine it took 5 minutes to get to that temp

I don’t even bother with the temperature thing

warm a few minutes . Check valve thing

wait for trickle

close it



ftr. 3.8 qts drain out in 10minutes

I add a gallon of maxlife.

I get rid of the excess during the check valve process

 

Sorry for my ignorance, but I have no idea about this. Is there a post that explains a bit more or can you elaborate?

 

https://www.youtube.com/watch?v=NUAuGmDGntY

 

It’s even listed as a “temperature range” in the procedure description. When warm, the fluid expands some and flows easier. Those two things make it give you the proper level when coupling the check plug. Doesn’t have to be exactly 115° F. Has to be in a range around 99°-111° or so IIRC.

How about a video
https://youtu.be/NUAuGmDGntY?si=4c5hCPIS0caOkv8G

 

Basically. Get a pile of the crush washers from the dealer, same size for drain and check plug. 24mm socket opens up the fill plug, no gasket on that one.

I wouldnt stress too much on the fluid level, get close and you’re likely good. I have a trans temp on the scan guage so it makes the checking procedure a ton easier