Originally Posted by stunt

I did my 1st fluid change 200 miles ago @ 133k, and now the transmission is stuck in 3rd or 4th all the time when driving.

It lurches when putting it in R backing out of the garage in the morning and again when putting it in D to drive off, but other than is is smooth, except for the slow acceleration with is probably putting a strain on the torque converter.

I'm guessing one or more of the valve body passages got blocked?