92 trannie trouble

hello everyone, ive got trouble. my transmission seems to slip at about 35-60 mph 3rd gear. the engine just races until i go faster. having read other threads about this it maybe a torque converter circuit. can i replace this or does the whole trannie have to come out can it be replaced from the bottom pan. i do believe it is a 4t60 transmission.

If it slips in 3rd only as you describe, it is not the TC, the unit has to come out.

Agreed... If its slipping 3rd, chances are it could be missing a thrust washer, have a damaged lip seal or just have a worn clutch pack.. Unless you are very very mechanically inclined you will want to have a trans shop do this...