Hello

I had the Toyota dealer (Executive Motors) do a drain and fill in my 2005 4runner in 2011 and I just learned from their receipt that they used T-IV, and my owners Manual says To use WS in this transmission.

Will this harm my 5 speed Aisin? The owners Manual says these fluids (i.e., WS and T-IV) are not compatible.

Why didn’t they use WS?

The D/F was done in 2011 5 quarts of T-IV.

Shifts fine with 147,000 miles but I‘m irked and I am calling the dealer service manager on Monday.

I am the original owner. The 4-speed Transmission uses the T-IV ATF according to my owners Manual.

AGAIN; Toyota The owners Manual says these (2) fluids they make are not compatible.

So, I have 45% of my fluid T-IV and 55% is WS.

No damage appears to have been done and it still shifting fine withOUT any slipping, but what should I do for my next D/F? Just switch back to WS?
I've contacted the dealers service department.

UPDATE: Dealer service department told me they use the T-1V all the time. The Manual says WS for 2005, but Toyota dealer that sold me the 4runner in 2005 says they can't get WS.
Tranny has 9 years on the T-1V and shifts fine. T-1V is nonsynthetic and WS is synthetic. Wonder what happens when you use Valvoline like many Toyotas owners use? Ha! Ha! Ha! I personally don't think there's much of an issue after 9 years on the T-1V and WS mix in mine.

Going to do a 3-5 quart D/F in another 40,000 miles. Going to use T-1V again. Just gotta measure carefully what you drain out and replace with exact amount.

Your transmission does indeed use WS fluid, but it's been 9+ years since you had the Toyota dealer do the service so I doubt you will get them to cover any damages if any.

That being said....you stated...."it still shifting fine with slipping"...so is your transmission slipping or not(?), if it is it could be from them using the wrong fluid or just from age.

If it is slipping it could also be low on fluid.

If it were me I would do a total replacement of the fluid (but not a pressurized flush) because just doing a D&F you will not get all of the incorrect fluid out of the transmission.

Hence, the term "Stealership"

The techs at the stealership are only trained on the newest cars. Unless you get some old-school tech that knows old 4Runners, you've pretty much got the FNG wrenching on your junk.

You should get that fluid out of there ASAP.

so thats why you were telling people on another thread to use T-IV fluid in their sealed 5 speed transmissions... glad i was able to point out for you that was the wrong fluid.

you should re-do your math, a drain & fill is only ~3.5 qts, the trans holds ~12qts, thats about 30%. you will need to do a complete EXCHANGE (not flush) to get all of the t-iv fluid out, not just another drain & fill.

& the fact you said the trans works fine with no issues just supports that using another fluid wont really damage these transmissions, granted using all t-iv fluid would probably hurt it, but a ~30% mixture of the wrong fluid in there for 9 years wont. point being using a correct aftermarket WS rated fluid like maxlife or amsoil etc wont hurt anything & likely is better quality fluid than WS.

hope you get the stealership to replace the fluid & own up to their mistake.


curious where you got 5 qts from? the manual only says the mileage interval, not the amount. pretty sure they mean a complete exchange of all the fluid at 100k miles (60k when towing or abused)

how are you measuring 5 qts at a drain? the pan on a 4runners sealed trans only holds about 3-3.5qts. toyota T 1v fluid?? these transmissions call for toyota WS fluid, or other fluids rated for WS use.

For all the experts - some posting with immense knowledge.

The Toyota service manager called and told me they have hard time getting WS, and they use T-IV in my 2005 (and their own 4runners)

He said for my next D/F I could use the 5 quarts of T-IV (it is a dyno - not a synthetic). So that's what I'm going with.

A simple drain and fill takes out 3 quarts. You got to measure what comes out and replace it.

Remember, this T dealer likely has a lot more experience than most "posters" and sees Toyota 4 runners every day.

147,000 miles on original transmission (doesn't slip/works fine/no offroad/seldom over 50 MPH so no overheats). Hope to get to 200,000 miles

Drain and fill with a filter at 102,000 miles at dealer

The original evaporator core was replaced at dealer in 2009 (they allowed me to supply the Denso part and charged me $350 labor). Why the OEM failed in 4 years Idoknow!

That evaporator core replaced in 2009 just failed again in 2020 but I found locaL AC place to repace with new Denso evaporator for $300 labor - and he can get it out through the glovebox and doesn't have to take down whole dash. I have to supply the Denso evaporator = $110 at Amazon.

see VIDEO youitube evaporator core 4runer - Bing video

yeah most "posters" here post FACTS & correct the nonsense some people post. like you suggesting T-IV is ok to use in a WS trans! so the guy at your dealership knows more than toyota or aisin??

the dealer has a hard time getting WS? they are a dealer & can get it just as easy as any other dealer. amazon sells it too!

& why do you keep saying 5 qts?? then say a drain & fill is 3 qts?

you do not measure what you take out & refill, yes that gets close but unless the fluids are the exact same temp it will be at a different level & you dont know it was at the right level before it was drained... especially if the guy is using T IV instead of the correct WS. proper way is to follow the correct fluid check procedure in the service manual with the trans to the right temp & drain via the check bolt until it flows at a trickle. anything else is just a guess.

but hey, sounds like you got it all figured out & trust your wacko stealership over the toyota service manual or aisin or members here that know the right way to work on their vehicles. carry on...

I can't comment on T-IV being ok to use in place of WS, but my local dealership tried to sell me WS for the 4 speed transmission in my 2004 that is supposed to take T-IV. As far as I know they aren't compatible so I just bought it from Ebay instead.

Also for the amount to use, man if you guys had a tranny dipstick like mine this wouldn't even be a discussion haha. Good luck to everyone, I hope you guys get it sorted out.

A mechanic I took my truck to once (and only once), who was a family friend, put some amsoil fluid in it. He said "yeah, it's what the dealer uses, I called my buddy at xxToyota and he said it's fine". I emailed amsoil about it and Amsoil said that specific fluid should not be used in that transmission and that I should change it as soon as I can.

The thing about stealerships and mechanics/techs, is that they can solve the problem or fix up your rig the day it's in there, and if it lasts more than a couple of months, they're off the hook for any accountability after that.

One should be aware that the transmission itself and its computer is REALLY good at getting you home even after something has or is in the process of failing. And it may run great for a long time with the wrong fluid (or even a failing solenoid or two), as anecdotal comments around the web and in shops all over will tell all those who listen.

Maybe it'll be fine or maybe it won't. Why screw with it, just put in the fluid the transmission was designed for and be done with it. It's your truck, your problem; if the dealer screws it up, you're still likely to foot the bill.

The damage to the valve body will likely be gradual wear due to the viscosity of the fluid not providing adequate pressures as its designed to. It'll probably drive okay but eventually fail.

I don't know why I replied to this topic, I just knew Captsolo would go solo and not take anyone's advice, being that he and his Bahamian dealer knows more about these 4Runners than Toyota, and then he post a video where the guy is working on a 2000 T4R which is not even close to the same as a 4TH Gen, the 4Th Gen evaporator housing is not only bigger but also oriented differently and there's no way it's going to come out the glove box hole.

But I wish him the best and I would get that mechanic to put that $300 quote in writing before letting him start the work and then he finds out he can't do it through the glove box!!

Man, you make no sense at all, first you question the dealership on why they used the incorrect fluid by quoting the Toyota manual, then state that the dealership has tons of experience, if you really believed that, why bother referring to the Toyota manual?

Cool

just for fun i called 2 toyota dealerships & spoke to a service dept tech, both places said you absolutely should NOT mix these 2 fluids. they both also said they would NOT use T-IV in a WS trans or vice versa at their service dept. i told one of the techs the story above & he literally laughed out loud!

to anybody reading this in the future... please do NOT follow what the resident expert above says regarding how to do a drain & fill or that its ok to mix these fluids!