Transmission Fluid replacement at 120k?

I fell into the trap of believing that I never had to replace my transmission fluid.

So I'm thinking of doing my first fluid drain/replace and a new filter along with a proper temperature fluid level check.

But now looking into maintenance videos I'm seeing people recommend changes every 60k. Some people are saying every 30k. Apparently the frequent refill cycles help to keep things clean, even though you're not completely replacing all of the fluid in the transmission.

I'm not having any trouble, but I've seen warnings that doing a drain/replace for the first time after 100k could dislodge built up gunk and suddenly provoke a break down or otherwise cause shifting problems.

On the other hand I've seen people suggest a series of frequent drain/replace to clean things out.

How credible are the warnings to avoid a replace after 100k?

My truck is a 2014 4.0L AWD.

 

Be prepared. You’ll get a lot of different opinions on here, just like an oil thread…

More than one Toyota tech told me to “leave it alone” when I asked if I should change out the fluid. Knowledgeable folks on here may tell you otherwise.

I had a 2015 that never had the tranny fluid changed, got 245k miles out of it, still ran perfectly when I traded it in 2019…

My 2019 has 148k on it presently, same story…

 

The refresh method makes life so much easier and is probably safer. I do that with tranny, power steering and antifreeze. Just get in a routine, keep a record and buy the fluids when there on sale. Bam

 

My 4x4 shop did a full fluid change with the help for the front trans cooler. We dropped the pan (it was clean) replaced the gasket/fluid. He drained the fluid in the front when putting fresh fluid in the pan till the color was new red. It take more fluid since you scrap some but you know that everthing old is out.

The last owner was a Master tech at Toyota so the truck was serviced on the clock. Everything was logged in the Toyota system. When i did a checkup the fluid was still red but on the dark side, no burn smell. It was time for the second service.

I still had some reserve, in the past i destroyed a transmission when changing the fluid... but i can said that after 10k miles i have no issue. I know gearcruncher use Lubeguard too, it seem a good product to put in when servicing and this can help high mileage tranmission since the product add.
friction modifier to help maybe glazed clutch.

The A750 is good transmission. It's not the most refined, but it last, mostly overkill for a Tacoma since it can output the Tundra V8 power.

Don't do a power flush (with the machine). The partial fluid change is good, but i recommend the full replacement with the tran cooler method.

Aisin recommend a fluid change every 30k Miles or 5-6 year, (sooner if you tow). I will myself stick to that interval, i trust the builder not the seller .

 

I’m a Toyota tech and I say just do it, however you want. It’s easy to over think.

The claims of problems after a fluid change are bs and stem from pre-existing problems.

A pan drop is a great point to start with.

 

I'd say change it if you want. I'm in the same boat, 125k and original fluid but recently had the tcase off and the trans fluid still looked great with no bad smell. I do plan on changing it soon though. FWIW I don't do any towing and the majority of those miles were on a close to stock truck.

 

Do it and if you’ve never done the rear diff, you’re in for a surprise

 

Nothing wrong with doing drain and fills. The A750F in my GX was basically untouched at 236k when I bought it. Started doing drain and fills with Valvoline Maxxlife at 250k when a shudder in OD started to develope.

Eventually ended up dropping the pan and replacing the filter screen also. Its shifting much better now than when i bought it. Nothing bad is going to happen by putting fresh fluid in.

 

I 2nd this. If your trans has been untouched for 120k+, I'd start looking at the diff and tcase fluid also.

 

My 08 started to have some trans slippage at around 110,000 miles, and after a trans fluid change it was back to normal. I'm at 190,000 miles now and have not had any issues with the trans.

 

100% do it, especially if the trans is still behaving and shifting good doing so will keep the trans healthy and provide a long life.

My process would be Drain pan, drop pan to do a very good cleaning including the magnets, replace filter screen, re-attach pan. Fill with 4 quarts, then do the proper "push out the atf from the cooler return line at the front of the truck ~ 2 quarts at a time" Id be inclined to use toyota WS (yes you can save money and go maxlife but the savings over 100k miles is negligible). Also getting a piece of 3/8ths clear vinyl tubing to run from the engine bay (with a funnel on the end) down the firewall to the fill plug of the trans makes filling the trans SO MUCH EASIER than pumping atf in.

The problem people have when they "get their transmission flushed" is when they take them to get presurized flushes which pull up all the contaminants from the pan and disperse throughout the trans. By dropping the pan to clean it and replace the screen, as well as using the trans itself to pump fluid like normal will avoid this issue.


Also 10000% do your rear diff if you already havent... at 112k it might be too late from pinion bearing (and subsequently gear) damage.

 

Can you give details about that event?

 

Do the trans cooler flush in the same session as the pan and filter change?

How many quarts total would that be?

Anyone happen to have a good video reference on that process? I’ll search myself, of course, but if you happen to have a link handy by a mechanic that you think is showing it right, by all means please drop it here.

Thx.

(btw: did the differentials and transfer case at 100k, sigh)

 

@Spif

If/when you decide to do a trans fluid change, I suggest that you use the genuine Toyota ATF and not aftermarket (valvoline, etc) This is especially pertinent if its a partial fluid change (drain/fill).

https://www.tacomaworld.com/threads...tic-transmission.63851/page-102#post-27091531

 

Yup. No use in mixing 4 quarts of new fluid after re-filling the pan from dropping it with the rest of the old fluid thats in the trans. There is about 11-12 quarts total in the system. I buy a case (12 quarts) and 1 extra to do a full flush.

After pan drop you fill with 4 quarts. Pump out and replace 2 quarts at a time for 4 times which will net you 12 quarts of fresh in the trans.

Now if you wanted to do the temp check mode at that point feel free. You will be very close to the proper level, but its a bitch to do the temp check mode, be low, then have to wait for it to fully cool down again to get back to that proper temp check mode.

This is where the 13th quart comes in. Dump it in before you do temp check mode so you are guaranteed to be decently above the proper level so you only have to do the check once.

Also, let the truck sit for an hour or so after starting it multiple times to pump fluid out, again this is so the truck is cold and you can get into temp check mode easily the first time.

Dont forget a new crush washer for the drain bolt and temp check bolt.

 

My short answer - do the flush.
Your owner’s manual (in maintenance booklet) states to do a flush for vehicles meeting ‘special operating conditions - off-roading, commercial use, towing, etc... It does not give percentages but many of us use the 60K fluid change recommendation as routine maintenance. Another common practice is to do a drain/refill every 30K. Either one, if done correctly, will help, not hurt, the transmission. ATF accumulates contaminates and that may, or may not, destroy your transmission. The point is to remove contaminated ATF as the culprit of a transmission failure. I flush my Toyota and Lexus vehicles with Valvoline MaxLife. Changing the ATF filter should be done by 150K, imo - sooner for those vehicles that use a paper element for the filter, our second gens use a metal mesh.

If you find large particles or metal flakes when inspecting inside the ATF pan, then that is when you should not do a flush because removing the particles in the fluid can lead to slippage. Many members here have done ATF flushes past 109K and none, to my knowledge, have reported issues.

 

I’m debating the same thing. Got a little shudder around 40MPH (guessing torque converter based on the number of threads here about it). A mechanic friend of mine said to do a transmission service but warned it could be opening a can of worms.

His shop won’t do them and recommended the dealership. Not sure they’ll do it with 111k on the truck. Gonna call tomorrow and see what a service guy there I know says.

 

It was a 41TE on a plymouth voyager 1996, the truck had the transmission rebuilt maybe 60 000km before and i wanted to keep it for some time. I knew the filter was replaced in the rebuilt so i drained the fluid and added to the dip stick level, did that 3 time if i remember over 4 day. 200 km later, when shifting in reverse to park at my house, something happened inside and cracked the case open, fluid on the ground, small aluminum pieces. The truck never moved again.... I know these was shitty transmission to start with. I knew there was a defect where a pin can go loose and drop somewhere in the clutch or planet assy, well the first rebuilt was because this problem happened, at the time it was my father vehicule. Never knew if it was my fault or something in the progress but it happened after the fluid change.

I have a 4T65-E on a Pontiac Montana where the trans started to do funky stuff after a flush. It was a power flush done a the dealership. 1000 km later the transmission started to shift very hard. No light but a max adapt code. The dealership wanted me to pay the labor to remove and inspect the transmission. The truck had like 112 000 km. At this point for the $$$ the dealer wanted just to see if they are at fault, a use one at the time with like 20 000km installed was cheaper. The funny thing is i never replaced the transmission, i said it will bleed oil before i touch that, the truck died the 19 December 2020, 10 year later with 184 300 km on the odo. Head gasket failure.

 

Likely because the transmissions dont have a dipstick and are a little more involved to get a proper fluid level. Just do it yourself, save the money its a pretty easy process just time consuming.

 

Let Toyota do it the first time