Transmission Fluid Change

My truck is coming up on 125k miles and I don't think the transmission fluid has ever been changed. I bought the truck with 114k miles on it from someone who works at Toyota. I am wondering if I should change out the fluid soon? My transmission does not slip, but I like to do preventative maintenance. If I should change it, should I do a full flush or just a drain and fill? Also, would you recommend having the stealership do it since it will be under warranty, or should I have an independent shop do it?

 

Just change it, change the entire drivetrain fluid. Either have a transmission shop do it or dealer if your saying it’s still under warranty.

 

A fluid change at 125k with an unknown service history is not preventative maintenance my friend.

I would disagree with the other guy about swapping it all out at once.

 

Just check it. Is level correct? Color correct? Otherwise leave it alone.


BTW, Having the dealership do it offers no warranty what so ever!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Oh, wait, forgot to mention.... So ever!!!!!!!!!!!!.....

 

I would do a drain and fill, and then repeat every 30k from there.

 

How would changing all the fluids NOT be preventative maintenence??? Why wouldn’t you change them all while your there?

 

I had mine changed at 100k.
I don’t know if they changed it all or or just drain and fill?
I know it was over $200 at Toyota Dealership.

 

For sure change differential oil though! Make sure you use the correct oil with LSD additive!

 

It's not that simple with these trucks and ATF. And I don't mean just the procedure in changing the fluid. A total flush on a damaged unit, that still has life left could kill it, if the level is good, color is good, I would leave it alone. If the fluid looks burnt, consult a pro, take it from there.

 

Your out of your mind. Define “not that simple”.

I’ve had my tranny, transfer case, diff, changed multiple times..... no problems whatsoever

 

It’s not as simple as draining and filling a differential but it’s not exactly difficult. It took me about an hour to do a full drain/fill/flush, mainly because of the crappy hand pump I was using to top off the ATF each time.

 

He asked if a shop or the dealer should do it. This is easy stuff for capable shop. I have no idea what you guys are talking about.... notice I mentioned I would recommend taking it to a tranny shop

 

If you change it yourself, don’t let your wife near it until your completely finished.
@sflanagan21

 

I did a pan drop, filter replacement and full +12 quart flush of mine at 125,000. No issues. I had only done a drain and fill a few weeks before, no other work had been done. Fluid was pretty dirty.

Do a drain and fill and a fluid level check first. That way you have experience checking the fluid level. If that goes well then do a full flush and filter replacement.

 

https://www.tacomaworld.com/threads/how-to-drain-refill-automatic-transmission.63851/

 

Preventative maintenance would be to change out the factory fill at 30k miles, and then to do additional changes at 60k and 90k miles (as needed).

But the guy bought the truck used and has no idea how the transmission was treated for the first 114k miles. It could have been used to haul horse trailers up mountains and still be on the factory fluid. ATF is never a lifetime fluid.

Changing it all out in one shot isn't always the best approach.

 

Just drive it till the transmission dies at 300K-400K. It'll die at the same mileage either way and the money saved by not changing the fluid every 30K will almost pay for having it rebuilt.

A couple of reasons.

#1 it is impossible to get it all out. Mixing old fluid with new fluid does next to nothing too improve anything, you still have old fluid in the transmission that quickly contaminates the new.

#2 As the internal parts of the transmission wear they work best with the viscosity of the fluid in there. Changing the fluid changes the viscosity of the fluid in the transmission. It is VERY common to see a transmission that was working just fine die within days of being serviced. Especially one over 100K. It is best to just ride it out.

The local transmission shop where I used to get mine changed no longer recommends servicing any transmission. They don't see the ones serviced regularly lasting any longer. The shops owner and his shop fore man are both driving full size trucks with 300-400K on the factory ATF. They tell me that the life of a transmission depends on the manufacturer. Some last 400,000 miles, others 100,000 miles and they don't see where servicing them changes that.

Wish they had told me that sooner.

My Tacoma's owners manual says never change the fluid, my Honda says every 60,000 miles and I followed those instructions. When they serviced the Honda the 2nd time at 120,000 miles the check engine light came on on the way home throwing transmission codes. Took it back, they reset the light and it drove fine for 2000 miles then it died. I spent about $400 having it serviced twice. Gonna cost $2K to be rebuilt. I could have saved the $400, applied it to the rebuild, and had the transmission last longer.

 

There is a thread on here that will walk you through a complete flush. I did mine, it is not difficult to do.

 

Some people around here spend huge amounts of time and money on high dollar designer lubricants....engine oils, diff/TC fluids, etc...changing them religiously. They'll flush the brake, power steering and cooling systems. They run only premium fuel...and so on and so on.

But when it comes to the transmission? "Yeah....fuck it. It's a lifetime fluid"

I don't get it.

I think people are just intimidated to do it. There's a certain amount of mystery to it. So they just ignore it.