Transmission fluid D&F at 120K

Okay, I'm not sure what to do here. My 2018 Tundra has 120k on the ticker, I'm finding a consistent drumbeat of people on the internet saying that you should perform a transmission drain and fill every 60k. I'm all for keeping up on maintenance on my beloved truck, but somehow I cruised right on by that target milage and didn't perform that service. So, what now? Some say it's too late, that I will cause issues if I start now, and that I should just leave it and pray it lasts the lifetime of the vehicle. I do lug around an OVRLND camper 100% of the time, and I'm rolling on 37" tires, but I drive it very gently. Should I leave it, or start doing drain and fills now? How many of you have high milage and have never touched the trans?
Pics for attention

 

The idea that you should leave it alone is malarkey. The fluid will only continue to degrade and become more contaminated with wear material, furthering wear on the transmission - the valve body in particular.

I am a firm believer in performing drain and fills as regular maintenance; it allows you to replace a portion of the existing fluid with clean fluid. The detergents and additives in the new fluid will helps to gently clean parts over time and replenish the depleted additives of the old fluid.

A flush, on the other hand, can occasionally cause issues, but it’s usually from the flushing method that dislodges debris that finds its way in to the valve body and mess up a transmission. This is where the old adage of leaving it alone comes from, and is grossly over exaggerated.

In your case, I would perform a drain and fill with every oil change (assuming you change oil every 5k) over the next 20k miles. That will replenish the fluid to something like 80% new; the math is easy I’m just too lazy to work it out right now. Sorry :/ But suffice to say, you would have clean, fresh fluid without compromising the integrity of the transmission. The d&f procedure is quite simple - if a little particular in some respects - and quite doable by most anybody that can change their own motor oil. Lots of write ups on the site here.

My ‘13 is at 230k miles of hauling and towing with some hard use bordering on abuse in there. At 180k miles I sent a sample of transmission fluid to Blackstone labs for analysis, in preparation for installing a supercharger. The oil properties were very healthy, but it was a little dirty from wear material and such. They recommended basically what I recommended to you above. Before that, I performed a D&F every 30k miles since new.

 

The service does look pretty straightforward, I’m kicking myself for buying into the idea that it was a lifetime fluid. I’m just concerned now that I’ll do more harm than good considering the mileage that I’m at.

 

Meh, don’t feel bad about it. You’re not the only one.

You would do more damage by not changing it, IMO. We purchased our sequoia used and I changed the transmission fluid around 100k miles. It was dark and stinky, but not quite burned. That was a year ago, and the transmission only got better with each D&F. Coming up on the third change soon.

 

The don’t change it if it’s old comes from old fluid being flushed (not drained and filled) and when you’re pumping close to 3-5 gallons through a transmission that has never been serviced, it causes problems

when doing just a drain and fill that negates most of that because you’re just replacing what’s in the pan, no flushing or dislodging anything; yes do the d&f but know that if you’re having problems now it potentially could make them worse (depending on the actual issue)

the actual service interval that I’ve read from a Toyota master tech is 60k D&F with normal use (daily driver) but 30k if towing; so I’d split the difference for heavy off roading

 

Oh and I originally thought it was bs that Toyota transmissions really do work better with Toyota WS, but it’s not, do yourself a favor and D&F with legit Toyota WS and not Valvoline Maxlife or something else

on paper the Valvoline is a better fluid, but the Toyota transmissions just like WS so much more

 

Are most of you going through the process of bringing the trans up to proper temperature and opening the fill straw plug? Or simply replacing the fluid taken out with the same quantity by measuring it?

 

do it the proper way by getting it to temp and using the check plug; make sure you pin the thermostat (if you have a transmission cooler)

 

I guess it’s time to drop a few bucks on a scanner tool

 

the carista one that most people use in here is cheap and is just bluetooth to your phone, it does require a subscription after a free trial I think, but is always handy to have

 

Technically you dont need a scanner, you can put the tundra into atf check mode and it will warm up the fluid and turn off a light on the dash to tell you when its the right temp, I can link you the procedure if you give me your year make and model

 

Awesome! 2018 5.7L DC 4x4 TRD SR5, I’m not sure what other make/model specs there are?

 

really just 4.6L vs 5.7L, but sometimes the temp numbers differ per years

 

There ya go, thats the ALLDATA procedure to check the fluid level on your truck, it tells the temperature if you were going to read off the scanner and it also tells you how to put the truck in atf check mode

If it were me I would double check that you understand/can get the truck in the check mode before you actually drain the pan

It calls for 3.2 Qts if youre doing a drain and fill

 

This is killer! Thank you man!

 

No problem! Hope it all works out for ya

 

Like @joseph_womack said, I’d recommend ATF WS from either Toyota or Aisin (the transmission is made by Aisin). Idemintsu is also a good choice. Several guys use the Valavoline stuff but I’m not a fan of multi-vehicle ATF and others have seen shuddering and issues when switching.

Also, even a cheap scan tool and the Torque App on your phone will get you ATF temps for less than $30. I use my head unit that is tied to the OBDII port via iDatalink Maestro. You could even use an IR thermometer on the pan to get you in the ballpark; it’s just needs to be in a temperature range.

The fluid check procedure is simple. I usually refill with 4 quarts then open the check plug when it’s warm (not hot) and wait for a strong trickle.

 

I plan to just grab four quarts or the Toyota WS from the local dealer, and I need a scan tool anyway. This one looks like it has a live data feed

$70 ANCEL AD530 OBD2 Scanner Diagnostic Tool, Universal Check Engine Code Reader with Live Data, Car Diagnostic Tool with Upgraded Battery Tester & All OBD2 Functions for 1996+ Vehicles, Upgraded AD310

https://www.amazon.com/dp/B07N66TTQG

 

what scanners can read toyota trans temps can be a bit finicky, not all of them can even with the live data feed

 

Okay, not as straightforward as I was hoping. That Carista unit looks solid, I just hate subscriptions.

 

It can be hit or miss with the readers, but most are pretty good. Saying that and it took Banks until earlier this year to get their super hoopty iDash to read transmission temps

But I’d suspect that one you have listed can read it.

 

I work at a shop and we have supplied scan tools, but I wanted to buy one for myself, so I got a TopDon AD500 but its like $170

They sell this one below for $39 but its got a coupon for $29, it has live data; and from what I remember the tundra trans temps are under engine live data because its an ECT, so it might show it

I can check tomorrow on where the temps are located but if this topdon works out its a pretty good deal for just engine codes and live data- Launch is also a good budget, linked below is their's too

$40 TOPDON AL400 OBD2 Scanner, Full OBDII Code Reader, Check Engine Light Scan Tool, Car Scanner with DTC Lookup, Clear Codes, Freeze Frame, One-Click I/M, Diagnostic Scanner for DIYers, Lifetime Update

https://www.amazon.com/Scanner-Read...tive,118&sr=1-25#averageCustomerReviewsAnchor

$46 LAUNCH CR529 OBD2 Scanner Diagnostic Tool, Full OBD2 Scanner for Car, Free Lifetime Upd. Check-Egine-Light Code Reader, 5 Years. Backup, Clear Codes, One Click I/M, for DIYers with Cars After 1996

https://www.amazon.com/LAUNCH-CR529...ix=launch+toyota+scanne,automotive,120&sr=1-9

 

Thank you!

 

You might consider adding $40 to the D&F budget and have a skosh of the old ATF sent off to Blackstone labs for a professional opinion of it's condition. Tell them what you've told us and they will give you guidance to decide a future D&F plan.

 

why is it necessary to pin the thermostat. I just added a transmission this weekend and followed all the steps to get it to temperature and pull the overflow plug until the fluid slows……but I didn’t have the thermostat pinned. Is that something i should go back and do?

 

I changed my fluid at about 120K miles. I did it via the transmission cooler line so I could replace it all at once without a flush. I didn't have any issues and that was 50k miles ago.

 

https://youtu.be/NUAuGmDGntY

Watch this if you dont have or want to spend extra for scan tool. Procedure in video.

 

Ok so I guess I know what I am doing this week / weekend…..need to repeat the process and pin the thermostat. Hopefully driving it until i am able to do that isn’t damaging anything

 

That car care nut video posted is an older one. In one of his newer tranny videos, he said his shop will not touch your fluid if it has over 100k on it. Not even a drain and fill. With that being said, if it was my truck at 120K, I’d still do a drain and fill. A little at a time is far safer than all the fluid at once.

 

You’re most likely fine, likely hood there was a massive air bubble in the cooler causing you to be low when you checked the level is impractical; but it’s still cheap insurance to double check it and is easy enough