Transmission Fluid Change

Seeking some guidance on whether or not to do a full transmission fluid change. I definitely don't buy the lifetime transmission fluid my 2015 Tacoma 4.0 V6 TRD Off Road has 175k miles and I have no idea if it has ever been done. I know the last owner didn't do it so it at least hasn't been done in the last 100k. I have read by some that doing it know could cause more issues. Thoughts?

Along the same lines, I am planning on doing fluid changes on both differentials and the transfer case. Not knowing the last time they have been done, someone recommended staying away from synthetic gear oil, should I stick to dino 75-90?

Thank you all in advance!

 

I change my fluid, and would here too. I’d rather fresh fluid and if there is a problem with the transmission, that I find it now, not 1000 miles from home when my choices for repair are forced

There are plenty of people who don’t, and don’t have issues

 

My 2015 V6 AT that I bought 8 mos ago had 185k, great carfax but no ATF service notated and it was dealer serviced every 5k miles. I did the full 12qt flush with Maxlife as per the great thread on this site in the sticky section on top. Been shifting and performing great for the last 10k miles. I also did a pan drop and filter change.
https://www.tacomaworld.com/threads...atic-transmission.68462/page-72#post-30440362

 

175? I'd do it... cause if it gets too old, they say don't touch it.. but in your case, i would. Mine is an 07 with 170 on it. I probably did it at 140 150.. there is a thread on here. https://www.tacomaworld.com/threads/how-to-drain-refill-automatic-transmission.63851/
I would make sure you are familiar with the process on getting truck to temp.
Crack all bolts before you drain.. you may and probably will run into rusted bolts.

 

I would do a drain, pan drop/filter replacement, and new transmission fluid (drain and fill) since likely never has been done.

 

I also did the filter.. but depending on op's capabilities, they may not want to go that far. But if you are comfortable with it, it's not very hard... I would also recommend that.. at the very least.. change the oil and.move on...

 

Welcome to TW...

 

I would NOT do a full flush. Only a drain - maybe 3.5 quarts. At that mileage a pan drop and filter change.
Look at the filter and see how much debris is collected.
See how it works after the drain, then drain again in a year?
My Son-in-law did a full flush and it ran horribly afterward on his Yukon. Sometimes the new fluid cleans parts too much to the point that the worn parts don't work properly. I didn't think is was possible until it happened to him.
I do a drain almost every 30K miles. 3-4 quarts, so what?

 

I would do the ATF filter change. Then, based on what you find in the transmission pan, make a decision on whether to continue with a full flush or drain/refill. There will be at least two magnets in the pan. If all they have is black fine crud, a full flush will likely not cause any issues. If you find clutch material or metal particles, a flush may cause more issues.

 

Thank you all for the guidance. I definitely feel comfortable dropping the pan and replacing the filter. I was already planning on ordering the kit from Blaupart's based on everyone's guidance about the fluid. Looks like I am proceeding with a drain and fill approach.

Anyone have any insights on whether to use dino or synthetic gear oil for the diffs and transfer case? I read on another thread not to use synthetic not knowing when/if they have been done. Thanks again, guys.

 

I just did all three, bought 75w90 Mobil 1 synthetic, Amazon had a nice deal on 6qt pack, they also have a crush washer combo pack, enough to do 2 or 3 full services.

Synthetic is what I chose but there's good info out there to keep using Dino if that's what's currently in there so it's your call.
You'll need a pump or gravity fed hose to fill the front diff, I used a 4 foot 5/8" OD hose and gravity fed it with wife squeezing the bottle, simple and no spills.

 

For Differentials read below links. I got dino and the ford friction modifier.
I don't know about transfer cases.

East coast gear likes Dino oil with a friction modifier.
see:
https://eastcoastgearsupply.com/files/PDF Files/ecgs-gear-oil-recommendation1.pdf

also read:
https://www.jeepforum.com/threads/synthetic-gear-oil-vs-dino-gear-oil-which-one-brands.1173782/

At least read and be informed about your decision.

 

Good stuff there, I'll edit my comment above

 

Friction modifier is required only for clutch-type limited slip differentials.

 

So, are you saying Tacos w/ electronic LSD, (which is what is in a 2021 Taco Sport 6 sp auto) , don't need the friction modifier?
Is that right?
I know Clutch vs Electronic are different.


Clutch-Type Limited Slip Differential
Features

• Mechanism: Uses a spring pack and clutches to manage torque distribution.
• Operation: Engages when one wheel spins faster than the other, transferring torque to the wheel with better traction.
• Performance: Effective in conditions like snow or mud, but can be less responsive than electronic systems.

Advantages

• Simplicity: Mechanical design is straightforward and reliable.
• Cost: Generally less expensive to manufacture and maintain.

Disadvantages

• Response Time: Slower to react compared to electronic systems.
• Wear: Clutches can wear out over time, requiring maintenance.

Electronic Limited Slip Differential (eLSD)
Features

• Mechanism: Uses electronic controls to adjust clutch engagement based on various inputs (throttle, steering, etc.).
• Operation: Can vary from fully open to fully locked in fractions of a second, optimizing traction dynamically.

Advantages

• Responsiveness: Quick adjustments improve handling and stability.
• Customization: Can be tuned for different driving modes (e.g., normal, sport, track).

Disadvantages

• Complexity: More components can lead to higher repair costs.
• Dependency on Electronics: Performance can be affected by electronic failures.