Tacoma with a jake brake

How does that work? Only way to not engine brake I can think of going to neutral or disconnect the converter.

 

Torque maps, shift points, and/or torque converter adjustments I'd imagine. I know I read it somewhere at some point but I just took a quick glance in the repair manual and didn't see anything.

 

Kdmax pro it

 

No one can help you here but guess. A video might help, but taking it to the dealer is even a much better idea as the truck is brand new.

 

ECT would still have engine braking...other than putting it in neutral or disconnecting the converter as stated above, the only thing I could think of to reduce engine braking would be if the VVT-i left the exhaust valves open longer on deceleration to reduce compression.

OP...does it only make this noise at lower RPM's? Or higher RPM's as well?

 

My guess...the torque converter clutch is not disengaging when it should or is engaged with too much force.

ECT is going to make flex lock less agressive or non-existent.

 

You're right. I guess I should have said the engine braking that goes beyond the typical, expected AT engine braking that people are used to.

 

Only happens at lower RPM, when slowing down and getting ready to come to a stop. (city driving) Does not happen all time, seems to happen at 3-2 downshift.

 

KDMax is like the damn duct tape of Tacomas

 

If you're coming to a stop, I believe the stock shift points will actually skip 2nd gear. 3 to 1 is what it's likely doing.

 

Fuel injectors shutting off during deceleration ?
All the 2nd gens do it every time you lift your foot off the gas pedal to save fuel .

Until your adaptive learning has tried its best to make you comfortable driving your truck , you may be in for a few abrupt downshifts .
Because your transmission is completely computer controlled , all the information can be found by connecting a tech stream scanner to the truck .
I suggest connecting the techstream and go for a ride with a seasoned Toyota technician .

Considering your truck is brand new , allowing a little time for the computer to create some adaptives may just be all this needs for rectification

Make them check the transmission fluid level . A lot of 2021 trucks are still a quart low directly off the dealersip lot . The AC60 series transmission enjoys a full tank of trans fluid .
A transmission that Kicks during downshift is a symptom of low fluid
https://www.tacomaworld.com/threads...be-low-on-fluid-directly-from-factory.405642/