Hello, all. And thanks in advance! My 94 SE 4t60e (180k + miles) seems to work fine on cooler days (less than 90 degrees fahrenheit or so) but on hotter days, after a long drive, I lose lock-up, then 4th gear. Left with 3rd gear, 3000 rpm at 65 MPH or so. If I shut it down, and re-start, I get full function for maybe 30 seconds or so, then it drops TC lockup, then O/D (in that order? not sure, but RPM changes twice). Check engine light does not illuminate. Hoping that I don't need a rebuild, not financially stable enough for that yet! Hoping it'* a valve body problem, or something not involving a total rebuild. Any help would be appreciated!

Thanks--Chris

Sounds like it might be overheating and choosing third as part of its limp mode.

How does the fluid look and is it up to the proper level?