Stays in 5th and 4th gear way too long

My 2019 TRD sport when on the highway stays in 5th gear and sometimes 4th gear for way too long. Most of the time it will be in a situation where it needs to shift to 6th gear at a certain point. But it goes past that point and takes about 30 seconds to a min to shift to 6th. On the extreme end at times it stays in 5th gear for the entire time I'm on the highway. For example I got onto rt 495 drove on it to my exit 20 miles away, and for the entire time it stayed in 5th gear. To be clear this is only happens once it hits the highway speeds of approximately 65 or higher. The 1st 4 gears are normally fine. The problem occurs once I get past 65, for example at 80 mph my odometer will read 2000 rpm's if all is ok. But when it is not ok it will at 80mph and read 2500 rpm which tells me I am still in 5th gear, this vehicles trans has 6 gears. This has all been verified by a Toyota FSTech who the dealership sent over for a ride along w/ me. This FST explained to me that this is a flaw that happens in the software w/ some of the models I believe he said from years between 2017 and 2019 Tacomas 6 cylinders. This software flaw was corrected in 2019 so some of them do not have the flaw. So naturally I ask him can they just give me the corrected software so I do not have this problem. And his answer was that there was no fix for it at this time. As he explained it, any changes to the software in any vehicle had to get epa approval 1st. He explained that epa approval is a big process that takes time and is very expensive. He explained that at this time it is not worth it for them to invest in this expensive process for so few vehicles that are effected by it. That a recall was not needed due to this flaw posed no safety risk therefore a recall was not mandatory. Then I explained to him that when I was traveling from Massachusetts to Canada that i did not feel safe being in the middle of nowhere. In fact while driving to Canada and I forgot to mention this to him, there were times that it was getting stuck in 4th gear at highway speeds of 80 mph. Hearing that engine revving in 4th gear at 80mph was quite upsetting to me, especially being in the middle of rural Maine, hardly a soul in site for many many miles. I thought I was going to break down. And the vehicle at the time was only 4 years old. Wondering if anyone first knows of this issue and also what I can do to resolve this with Toyota? Now I have contacted Toyota customer service and I do have file on it with them. I will be working next with a Toyota "customer care" person. Not so sure how well it will go. I wish I had more info on what I can do.

 

How many miles on the spark plugs?

 

OP - when you say "highway", does this mean flat or other? If you have any inclines I would be saying it could feel like it is 'stuck' in a lower gear at those speeds for quite a distance. What were some of the geo conditions you were seeing this at?

 

A tune should fix you up nicely.

 

ECT on or off?

 

@cantquit1 you can get a fix by getting an EPA approved tune from https://overlandtailor.com/3gt-ott-custom-tuning

Find your local tuner here: https://overlandtailor.com/retailer-locations

 

turn off the cruise control

 

He mentioned 495 and massachusetts.. i am from this area, the roads are not hilly nor are there too many challenging inclines, heck i just took 495 to get to work, geo conditions shouldnt be an issue for him there. He also mentioned Ma to Canada and middle of maine, i know the roads in new hampshire, vermont and maine to be a bit more hilly but i have driven my tacoma and a 22 sienna in these areas in the past 2 years and have not had issues that it would make the gears drop down

I think we need to know how many miles he has on the truck to know if it is a preventative maintenance issue

 

I'm not familiar with the 6-spd automatic (mine is a 2nd gen 5 spd). Are 5th and 6th both overdriven? My 2011 will shift out of 5th fairly easily and sometimes be slow to shift into 5th, depending on the load (including up hill as well as weight). I chalk mine up to be torque related, the electronic control keeps the tranny in the lower gear until the load is reduced or the measured torque is high enough to signal the change. Overdriven gears are more sensitive to torque changes, and the 3.5L engine makes its torque at higher rpms than the 4L.

 

Mine will stay in 5th for awhile if there’s a decent headwind, and it’s even tuned. I don’t think it’s that big of a deal.

 

I've noticed with mine that it is way more shift happy using cruise control on a road trip. Cruising 75mph, I found myself locking it in 5th gear so it would quit shifting between 4th, 5th, and 6th all the time.

Texas is not exactly known for a lot of hills either.

I'm hoping an OTT tune and a regear will fix this...

80mph in 4th gear is fine. Won't hurt anything

 

Thank you all for responding... Ok so to update more info about the truck, yes it happens mostly while in cruise control at these high speeds. This happens when driving locally all the time once I get up to the high speeds it staying too long in 5th gear on a 6 speed trans. That trip to Canada is when it was at its worse, it was happening getting stuck in 4th gear at 80mph, which is very high revving and damaging to a transmission and motor for long enough periods. Not to mention the extra gas I'm using as well. At that time It had less than 69000 while on trip to Canada and was still about 4 years old. A relatively new truck, so the main point of all this is is what was said by the Toyota rep or FTS person that came to do a ride along and witness it happening. His response that represents Toyota was that this was a known issue. And that they could repair it with a software adjustment. But due to laws it needed approval from the EPA 1st before making any software changes. And getting that approval was a costly time consuming matter. It was deemed not worth it due too few vehicles experienced this problem. Half way through 2019 they changed the software which corrected this issue. So I said hey can you just give me the second half of 2019s sw and he said they are not allowed to do that either w/o approval from the EPA. You can only put in software that was approved for that vehicle. In fact the vehicle will not accept it if you tried to force it in. They are designed that way today, he told me. I think he said it was the 2017 to 2019s that had this issue. So hopefully I will be speaking with this "consumer care" person from Toyota today and let you all know what Toyota will do for me.

 

Stock truck?
As mentioned, a decent headwind will create enough resistance to downshift.

 

I have a stock Sr with the 2.7 and not even upgraded wheels and tires yet and this truck is a dog. If I set cruise to 80 it’ll gear hunt forever between 6th and 5th but found the sweet spot around 77mph for cruise. Better to just do it myself the truck like you said, stays in a gear too long, I’ll just give it a little more gas to push it to the next gear if need be.

Im in MI and roads aren’t super crazy, pretty flat with some normal inclines - would hate to see this truck on mountain passes out west, I’d probably never use cruise and have ECT on

 

Manual swap should fix that

 

This is not 5th gear at 2500 rpms. Ive tested lots of tunes to make the truck to hit 2500 in 5th.
You are in 4th and there the upshift issue from 4 to 5 th at high speeds.
Use Smode to upshift when get stuck.
Get a basic obd2 phone app to sorted out the issue

 

So for my vehicle I was lucky enough to report this problem at 59,988 miles so I was still under drive train warranty. Since I paid for it I would like them to fix it. Normally moving it in/out of Smode or putting it in 6th from smode does make it up shift. But on that extra long extra hilly trip through Maine it was remaining stuck in 5th on the highway at 80mph no matter what I did. For a few times it remained stuck in 4th gear as well, which was scary making my engine race like that. Using the Smode on that occasion however did not work, it would not make it upshift on that occasion. I do think I tried turning on the ECT to see if it helped in some way and it did not. Honestly I just wish they'd fix it. I invested a lot when I purchased this truck, what about that? Shouldn't that mean something? Part of the reason I'm writing this is that if they see enough people complaining about it they may fix this problem.

 

Tune it and be done.

 

Tune it
Get a mnaual
Change differential gears
Or
Slow down