99 overdrive problem

My 99 just started to have some probs with the trans. After about 30 miles or so at about 60-70 it seems to have problems shifting (feels like it's slipping) but it doesn't do it all the time. seems like when it gets hot.
Otherwise it's fine. It doesn't slip any other time. It has 119k on it but I serviced it since new.

It should be about time for a swap....Mine went out at about 55k. But the only way I could tell it was slipping was when the AC was on at highway speeds, The tach would jump hmmm... maybe 5 to 800 rpms more than nomal when the compressor kicked in and out. And a check engine light there soon after. I would guess with that many mile the converter is starting to slip. My :2cents: