My transmission shifts fine when cool or warm. However, after about half an hour, it starts shifting hard. From 1st to 2 and 2 to 3rd. Also when it is hot it downshifts abruptly (maybe I notice the downshifts more because it is a hard shift).

Today, on my way home it stayed in 2nd gear and refused to go into 3rd gear. Now this is strange, I pull the car to the side of the road, put tranny in park (engine running), applied handbrakes, pop the hood and check the fluid (probably took about 2 minutes in all). There was almost no fluid on the dipstick. I thought, what is going on, since there is no leak from the transmission.

I then put back the dipstick and walked over to my other car and got a quart of ATF, with funnel and came back (maybe about 2 minutes). When I pulled the dipstick to pour in the ATF, I notice that the ATF is back!!

I know nothing about Trannies but where could the ATF have gone? And could this be the reason why tranny would not shift. Maybe ATF was "stuck' somewhere", or was not flowing well when tranny is hot.

But I thought that when tranny is hot, the ATF should be flowing well. Is my tranny shot?

BTW, fluid smells ok, no burnt smell, car has 140K miles.