Transmission adaptive learning?

I've owned my 2023 Tundra for one year. I took it in for the scheduled 5k service and asked the dealer to check out the hesitation I noticed when stepping on the pedal from a stop.

I was told that the software was updated and that the truck would have to learn my driving habits to correct and eliminate the hesitation.

Is this bullshit or what? How long will it take to learn my driving habits?

 

If you were having long delays and they updated/reset the tcm, you *may* see some improvements after 500 - 2500 miles.

If it truly is a learning issue (which I don't think it is), I think the learning algorithm is shit.

 

If you want to see if you can speed the learning up, what I believe to be the actual process is to slowly accelerate to 32mph or more then decelerate slowly back to 0 a few times.

 

Thanks all. I'll give your method a try, rlc177, and report back.

 

I have a '22 Mach 1. The tranny has the same "learning" feature. It goes away.

 

I gotta really be easy on my take offs or I get way too much throttle. I’m ok with it tho. I let the engine see the entire rpm range tho so maybe that helps.

 

The adaptive learning does not “learn your driving style”. This is a myth that has existed since the first electronically controlled transmission. The transmission adapts to changes in the hydraulic fluid (the ATF) due to age, contaminants, etc. and adjust how the hydraulic pressure is applied to the clutches that shift the gears. If this control is static for the life of the transmission, it would cause improper shift operation like jerky shifts. You can test this if you want by disconnecting the 12 V battery which clears any learning in the ECUs. You’ll notice some harsh shifts initially but after some time the shifts will get smoother. There are a few learning procedures out there but here is a pretty quick one I pulled off another website:

• 0-80 MPH @ 25% throttle position, then slow down and come to a complete stop.
• 0-80 MPH @ 50% throttle position, then slow down and come to a complete stop.
• 0-80 MPH @ 100% throttle position, then slow down and come to a complete stop.

This may not help with your hesitation issue since it won’t change how the shift is actuated in terms of duration.

 

Yeah there is very little "learning" and it more like select what you think is the best table from these set of torque tables based on some logic kind of thing.

What I know from 3rd Gen Tacoma, there is a table called "Optimal Torque for Shifting" there about 12 different tables, depending on the "AI" it can select different tables and some of them are kind of bad, leading to the unpredictable shifting behavior a lot of people experience over there. There were kind of a few workarounds like resetting the TCM memory and that sometimes stopped the cycle of selecting a bad table for a while, or always using ECT or S mode which used a single table all the time.

In the tundra the only drive modes I think use a fixed table are Tow/Tow+ and 4WD, all the others probably use some selection routine of a dozen or so maps.

Ultimately on the 3rd gen because the ECU wasn't encrypted there eventually were really good aftermarket calibrations that made the shifts more predicable by refining the tables Toyota wrote.

 

rlc177, I just got back home from a trip with my RV and noticed that in Tow mode, first gear to second is shifting very jerky. Since my TCU was updated few weeks ago, I think it can be partially the case. After returning home, I disconnected my RV and went for a test drive to assess the situation. When transmission is in regular mode, it shift first to second smooth like butter. But as soon as I switch to Tow mode, it jerks very hard on a first to second shift. Also, hesitation at the rolling stop is back and very noticeable in tow mode.

I am thinking of bringing it back to toyota dealer next week...

 

Tow mode is designed to give quick hard shifts. Your don’t want the trans smoothly sliding between gears with a heavy load.

 

On my way to the camp site it did not do that. I am not sayin the shifts should not be quick. But I think it is a bit too jerky only from the first to second. It makes me feel uncomfortable..

 

There's been posts about jerky shifts after receiving the recall, For the most part I think most peoples jerkiness went away after 100-500 miles. I know on my 3rd gen Tacoma it would drive like dogshit for like 3-4 drive cycles after resetting learning values and transmission memory and go back to normal within 100 or so miles. Because the driver has now driving their truck a lot there is memory developed so its more noticeable than maybe when the truck was new.
In terms of the learning process its not a actual milage, but rather certain conditions need to be meet so each driver will be a bit different. Tow mode has very firm shifts for me but nothing felt out of sorts.

It would probably be best to take it to the dealer and do a test drive they can refer to internal docs on the proper drive procedure and report problems to Toyota. It also very important to report and document any issues especially in the 12 months or 12000 mile period of ownership for your own protection.

In terms of the overall hesitation issue, I think there are probably several different glitches so everyone experience is slightly different.