okay first off its a l98 5.7 tpi stock auto no run ability issues

i noticed last nite 2nd and 3rd would be ether late or not shift.

today i noticed 2nd is fine but 3rd will ether, shift late, not shift or shift fine

but under WOT no problem and if its in 4th and it down shifts into 3rd no problem

besides fluid what should i check etc?

thanks guys

 

it will down shift from 4th into 3rd sometimes.

is the modulator for the transmission internal?

i had thought there was an external one controlled by vacuum.

 

some times it does shift and seems to buck or lose power when its suppose to shift at random times.