Should I change my transmission fluid at 111k miles??? Regear?

Hello,
I have 2013 Tundra 4x4 and I'm having trouble finding online if I should change my transmission fluid. It is at 111,xxx miles and has never been changed from my knowledge. I see tons of contrasting opinions online, so I'm a little confused. Some people say to do a drain and fill, others saying to do a flush, and some saying not to touch it at all.

I have been running 35s for the past 10kish miles. I bought the truck at around 97k miles with it on 33s. I have no idea if tire size actually makes a difference when it comes to how bad the fluid is, but I thought I would add it just in case. Also for the record, I do have somewhat of a heavy foot. Despite all of this, I have had no problems with the transmission except for it shifting weird sometimes because of the tires.

Also, I would like to regear my truck but once again, there's many contrasting opinions on whether I should run 4.88s, 5.29s or just keep it stock. I plan on running 35s for the most part. Not as important of a question, but I thought I would ask.

Any help or recommendations would be appreciated. Thank you.

 

I would do a drain and fill.
If you love the car, maybe drive a week or so and do another drain and fill.

I did that with a SUV (2 drain and fill) and it shifts so smoooooth. Lol

I'm sure experts will disagree!

 

+1 for drain and fill. Despite what some claim it is not lifetime fluid, heats/cools just like engine oil. I have a recommendation saved to do it at 60k per the car care nut guy. I'm going to do it every 50k.

 

Fluid dynamics man...is an old stale frosty snack better than a fresh one? Drain & fill, repeat as necessary...

 

Clean fluid is always better that dirty fluid.

 

Drain and fill ONLY! Keep it in S4 as you putt around your local streets or tow a load and throw in D as you proceed down the highway.

 

+1 or +2 or +3 (wherever I am in line) for a drain and fill. Easy enough to do. I did it at about 90k miles and it shifts so smooth. Will do another at about 110k miles. Consider using the Toyota World Standard (WS) tranny fluid.

 

Trans fluid and motor oil are very different. Motor oil is subject to heat stress, but also exposed to products of combustion which get the oil dirty quickly. Trans fluid is exposed to very little dirt or contaminants, but is heat stressed. Trans fluid also contains additives to help with torque converter performance. Over time these additives get depleted, or break down. You also do have some internal contamination of the fluid from Torque converter wear. A drain and fill will remove about 1/3 of the fluid in the system and replenish with a fresh third that has fresh additives that will aid the torque converter function and help keep the internals clean. Reports here are that letting the truck sit for more than an overnight will allow more trans fluid to drain down into the pan and some are getting as much as 5qts out. I’ll be doing a drain and fill at my next oil change (80k miles) and hope to leave it overnight to get the maximum amount exchanged.

 

I had the same thought about draining out overnight but was wrong. 4.5 quarts total drained out very quickly, maybe 1 hour. No more than 4.5 quarts was in the bucket by the next morning. I also pinned the thermostat open the entire time.

 

Don't do a tranny flush. Just drain and fill as others have said. Being that its never been changed a flush could introduce some serious issues if you were to go that route. I would say make sure you use the technique with the check valve (as opposed to just measuring what came out and putting that amount back in) in order to make sure you have the correct amount of tranny fluid in there. Then if you do another one in a month or so you can just measure what comes out and replace since you are pretty confident at that point that the right amount is in there. I just did a drain and fill on my 2020 with 30K miles and I'm pretty sure it was low from the factory, it was always a little rough shifting when cold and when going from reverse to drive. I took out just a hair under 4 quarts and after using the check valve ended up with about 4.5 quarts being put back in.

 

That's what I was leaning towards. I did see a lot of people say to do a drain and fill more than one time. Thank you!

 

I just took ownership of '07 TRD with 185k. Transmission was "serviced" at 100k. I have been researching with much conflicting info on the procedure. After reading this thread, I think that multiple drain and fill is the way to go.

 

I'm going with that too.

 

1st, do drain n fill. Inspect the condition of the fluid. Red or brown and it smells like transmission or hydraulic fluid, then it’s good. Black or burnt smell, you have a problem and may consider putting that old fluid back in as new fluid will cause issues.

2nd, a few thousand miles after you’ve done a drain n fill, I’d suggest a pan drop and filter screen clean or replace. Get a fresh Toyota gasket and new o-ring for the filter screen. Clean the pan thoroughly as well as the magnets. Inspect for any abnormal debris or big chunks. Fine mush on the magnets is normal.

3rd, why the hell not, after a few more thousand miles, another drain n fill, and put some trans max anti shudder in, one tube will do the trick.

4th, after all this, depending on your driving conditions, every 15k to 30k do a drain n fill.

 

FYI, here’s the anti shudder additive. Also, always use new crush gaskets on the drain and check plug. As for the fill plug, don’t use a 24mm, use a 15/16ths as it fits much tighter and you won’t strip it.

$15 Lubegard 19610 Dr. Tranny Instant Shudder Fixx 2 Ounce 2 Pack

https://www.amazon.com/dp/B00337DUEU

 

Loosen fill plug BEFORE drain plug, don't want to drain and can't fill. A CLEAN long hose up to the engine bay with a CLEAN funnel or a syringe type pump such as Mightyvac hand pump can be used for the filling process unless you have another method available such as an actual trans fill pump or DIY weed sprayer version, all will work.

 

A variable to consider is the temperature of the fluid since the correct volume is dependent on the temperature. I'm wondering if an IR gun pointed at the transmission pan after warm up is a good idea when draining the excess fluid after refill. BTW, what is the correct temperature?

 

Before my 2020 I had a 2016 with 100k+ miles. At 100k I did the DIY drain and fill where everything is cold (I think it was around 3-4 qts). Definitely shifted better after that and I wished I had done it sooner. With my 2020 I'll be doing a drain and fill every 50-60k.

 

Is it necessary to open the cooling thermostat by depressing the pin with a wire or can this step be omitted and do a simple drain and fill?

 

At temp 1 should be between 99 and 111*f

It is necessary to pin the thermostat to circulate the fluid

I’ll see if I can get to running TS to see fluid temp and its relation to pan temp with an IR gun

 

We pray to St Petr for he is the knower of all things Tundra....

https://youtu.be/7w1gvELvQf4?si=Vv_w7RyW4vs7m_jO

 

Plus eleventy-seven for a drain a fill.