Feels like it is missing when maintaining speed

Hi all
New member first post. I have a 2021 Off-road - Automatic 15,000 miles. I am original owner I bought it new. I had what I thought was the common gear hunting issue so I had the KDMax 10.0 tune done.
While I noticed an improvement it did not seem to fix my issue. When I am driving and just cruising along trying to maintain speed with my foot lightly on the pedal the truck feels like what I can only describe as a miss or stutter. If I lift off pedal it goes away. If I give it more throttle goes away. This will happen at any speeed. I can be goi g down the highway at 75 and just trying to maintain my speed and it will start its sputter, miss or whatever you want to call it. My only true fix before and after the tune is put it in drive and slap it over to S(4) so it never goes into overdrive. I took it to Toyota and they gave me the run around saying oh you lifted it - you put off road tires on … blah blah blah. My fear is that there is something possibly going on with torque converter or transmission. My thought is remove tune and keep complaint to Toyota. Or should I dump it and run away ?
thanks in advance

 

How many miles? How up to date are you with common maintenance, clean throttle body, MAF, spark plugs etc.

 

Sorry should have mentioned I bought in new in 2021 and it has 15,000 miles. Only maintenance done so far is oil changes and tire rotation.

 

Not high enough rpm to get into the torque needed to push our aerodynamic brick down the road.

Do the calculations for torque at the rpm the engine is turning at 75 mph.

Factor in parasitic loss for all aspects of the drivetrain.

Now calculate the resultant wind resistance of the front of our brick on wheels.

What you are left with is a very small amount of torque left to maintain.

Engine needs torque which equates to downshift and raising the rpms.

Transmission is saying no don’t downshift we need to maintain fuel economy.

Torque converter doesn’t have enough pressure to maintain.

You feel the results.

Tune doesn’t mean squat when in 6th with a light throttle to maintain. Torque at given rpm is the same.

 

It does it at any speed never had a vehicle act like this.

 

Unfortunately it is a normal 3rd gen “problem”. Some trucks do it worse than others. My old 2020 Trd sport did it so bad the entire can would start shaking . Dam shame and another one of the 3rd gen tacomas quirks or at least some of them. Zero fix as far as I know. I’m thankful my 2023sr5 doesn’t do this. It drove me insane on my sport

 

It is driving me insane. I hate it. I drive around in 4 so it don’t do it.

 

What is the throttle level is your tune?

 

Sorry buddy I feel your pain. Not sure what to suggest other then selling it or pleading your case with Toyota or just living with it

 

Medium setting on the tune

 

My 6MT does it too. Seems to be getting worse. 2600 miles. I haven’t researched too much yet but I wonder if plugs have any effect.

 

Bad gearing and a gutless engine

 

What lift and tires are you running?

Also, did it do it before you modified your truck?

 

It has wild peak AT3 icon stage 2 2” lift
Mods were done the week I bought the truck.

 

Try sport.
Also, recommend to get a phone based obd2 app to see all parameters. Helps to rule out any issues

 

What parameters are helpful to keep an eye on? I use Torque to watch SLU, Lockup, AT temp, and RPMs. This problem is repeatable for me, but seems to happen over a wide range of parameters.

 

Make sure the spark plugs are tight.

 

When did this driving behavior start?

it does sound like the usual economy/low emissions upshift just taking the motor to a range it’s not fun to drive,,, the new world order

 

Accelerator position, throttle position, engine load, gear. Typical torque converter shudder happens when tc is fully locked, high engine load, low rpms, accelerator position increases, but throttle position stays the same or slowly increases. The downshift happens when the engine load reaches 100% load(dead pedal).
Want to rule out misfires, add all cylinder misfires and check mode $06 after the drive to see which cylinders misfired