2006 Tundra Transmission issue

I have 214k miles on it and the transmission is now acting up. Slow getting up to speed, seems like if I play with accelerator it helps. Then it appears that is will not go into OD. I drove it 250 miles last weekend and on steep hills it will only stay between 25-30 mph. Is the transmission gone? Thanks

 

Has the fluid ever been changed or checked?

 

yes, just did a flush about 2 weeks before this last weekends trip

 

Did you do an actual flush or a drain+fill? Was it acting up before this? Most people don't recommend doing a flush on a high mileage trans unless you know the history. Do you know if the transmission was ever serviced prior to this?

 

Toyota did a automatic transmission fluid exchange, after we noticed something not right w/transmission. We are not sure if any work was done prior to us buying it in 2017', previous owner did not alert us to any work.
They also told us transmission needed work or replacement. I am searching here to find out other experiences. Thanks