99 4Runner Tranny?

I have a 99 4Runner SR5. I have an intermittent problem where when I start from a stop the engine will rev but the wheels don't move, then all the sudden, it will lurch and go.
Sometimes it doesn't happen at all. I can even go days without it happening but then it will do it for a couple of days in a row.

I had a major service done a few months ago and they changed the transmission fliud then.

Of course, when I last had it at my mechanic, it would not do it.

Any thoughts?

Did you flush the tranny or just drop the pan and replace the lost fluid? The torque converter and valve body hold alot of fluid that isn't exchanged by dropping the pan. If you didn't, try flushing the tranny through the heat exchanger lines.

I don't know if that is what my mechanic did or not.