2005 Tundra Shifts hard

[StPete84]

I recently purchased a 2005 Tundra that shifts hard. It’s most noticeable around 35 MPH. I’ve found if I turn overdrive off until about 40 MPH it shifts much smoother. I’ve had the transmission fluid flushed, but it hasn’t made a difference. I’m not sure if this is worth fixing or if just turning overdrive off until I get up to speed is sufficient. Thanks.