Engine brake, can it be disabled?

In all those miles you never bothered to understand the feature you use 80% of the time? Just correcting bad information

 

I can downshift and rev OR upshift for lower RPM and it works well for me. <shrug>

You can stick the 'bad info'.

 

You’re not controlling the upshifting other than allowing it to happen. The computer ultimately decides. If you’re driving around at 5 mph and click it from S3 to S4, you didn’t upshift it to 4th gear…

Only reason it seems like you’re controlling the upshifts is because the computer was already ready for the next gear and so when you clicked it up a gear, it shifted.

 

2020 TRD Sport 4x4 6 speed auto.

Using s-mode wont force an upshift, it just sets the limit of available gears.
The transmission wont up shift until it is good and ready to, no matter how you set it.
Try putting your shift selector in s-6 at a dead stop and see if it tries taking off in 6th gear, then get back to me on it.

 

Or you can admit you didn’t read the manual and made an incorrect assumption based on upshifting at high rpms

 

There is or was a TSB to address shifting issues relative to 6 speed automatics. I was very unhappy with how mine (2019 TRD 4x4) and had the update installed and it made a world of difference. Check and see if yours is covered.

 

Move along jackalope. I told you.. the truck downshifts when I want it and upshifts when I want it to. Why the F would anyone attempt to select 6th while sitting at a dead stop. That's just stupid.

 

It’s never a bad thing to be more correct. What you said wasn’t correct.

 

When I have the cruise control engaged while descending a reasonable winding grade, the transmission will incrementally down-shift to seemingly control the speed. I recall reading somewhere that it is the A750F Intelligence working with the cruise control, braking, and steering input doing its' thing to maintain/control the speed. When the cruise is disengaged, (switch or brake application) the activity ceases. I suspect it's also using throttle position to assist in keeping things under control.

 

To find out if s mode forces the truck into the specified gear or not?

Spoiler

It doesn’t. It’s an upper limit control like the manual explains

 

Just because you select S-6 does not mean it will be in 6th gear.
You can select S-6 at anytime, even at a dead stop.

 

That's Toyota AI-SHIFT logic. Found across many models, including 4RUNNER.
One of its quirks in 3rd gen is delayed 4-5 upshift after climbing a hill or steep incline at speeds 60 and above. Possible due to ASIC active state. S mode overrides it.

 

Thanks for the response. Nice to hear someone else is familiar with it. It also adjusts to driving style: country "old man" mode adjusts with earlier/easier up-shifts. Go through a few on-ramp panic merges with more pedal or force it and it provides an earlier/firmer kick-downs and then holds them longer.

The 4.0L loves it and answers/responds accordingly.

 

I am going to have to pay particular attention. I am in the ANF in Pa. and have noticed it several times but I don't remember if I was in D or S at the time.

Some have mentioned to avoid touching the brake, or to keep my foot on the gas, or to just touch the gas when this happens. I'm not interested trying to remember how to avoid it, or what to do when it happens, I just want it to go away. I'm sure people all drive a little different, for me, driving should not require a list of dos and don'ts on how to react if the truck does something for no reason. I guess I need a tune

 

Good to see/hear someone else noticing this "feature". I thought it was my imagination, until it repeated the same behavior (more than once) the same downhill on the same stretch of road in the White Mountains. Frequent downhill braking definitely seems to trigger it as do steering corrections. Somewhere out there on the web, it mentions this intelligence on a site with info on the Aisin A750. Next time I notice it, I'll try shifting it out of "D" to see if it makes any difference.

 

I never read the manual(s). Most of them still have the seal on them or are still in the heat-sealed plastic bag.

 

Interesting! Your quote of my post added some text that is not in my post? "sometimes, but it actually works very well."