Transmission acting up?

Was backing out of a flat driveway earlier and my 2017 SR5 (v6 auto.) Felt like it was accelerating a bit on its own it's reverse. Like it wanted to reverse 15+ mph with no throttle. Then while driving off, the shift from 1st to 2nd gear was rough and it made a bit of a loud clunk noise. After that everything was fine. But I know my truck has done this in reverse a few times before, not as bad though. Is this something that I should be concerned about, or check something?

 

Ever had the fluid level checked? Some 16 and 17’s came low from the factory.

 

Don't know about the bad clunk, but was the engine up to temp, or cold ....it will idle higher rpm at times till warmed up enough.

 

This, give a few seconds to idle down

 

My 16 still shifts erratic at times but have come to expect it.

 

^this

do a drain and fill

 

I'm at 38,000 miles, is my truck due for this anyways? Is there a filter to change as well? I have no idea if the previous owner changed trans fluid before, I bought the truck at 32k miles. Last noob question ...is there a specific auto. Trans. Fluid that seems to be the best, or "go to" stuff for this truck?

 

My 16 was low from the factory. Even a fraction of a quart makes a noticeable difference in these trucks.

you don’t need to worry about a filter. There’s instructions for the whole process in the DIY sticky. I’ve used amsoil personally.

 

I use run amsoil atf in my tundra...it ended up causing lazy shifting points. Had to have it flushed. After that only mobile 1 atf synthetic.

 

Yep. Check fluid level as mentioned.

 

Will be doing a drain and refill very soon.
But yesterday, while going through a drive-thru, my truck was "acting up" way more than what I've noticed any other time. In drive while on the brake pedal, allowing it to creep forward, the engine was revving on its own (not high revs, maybe 2k rpm? Not sure), causing the truck to want to surge forward. It would do this every 3-8 seconds, but only if I was letting it creep forward from what I remember. and if I let any more pressure off the brake and wasn't careful, it could have caused the truck to drive right into a curb or structure in that drive thru.
As mentioned in my first post , it does this in reverse sometimes too. Not in etc-power mode any of these times. Is this normal for 3rs gen Tacomas to do this, or is there something going on? Does it have anything to do with the tune/would the OV tune fix this issue?

 

My 2018 has been doing this from day one. I got in contact with the dealer. They test drove it and said yes it does this but we have NO remedy. This is how Toyota designed it so they tell me. I call BS!! They now have it documented. Good luck!

 

My 2020 sounds the same as what you have , but only if the engine is not up to the correct temp. Otherwise after a minute or so all is normal like any other automatic vehicle.