700r4 transmission problem!!
 

ive got a 91 s10 blazer with a 350 small block with an elderbrok tunnel ram with to holly 450s set up as a street/ drag truck but recently my trans has been screwin up ive checked tpb ( throttle position bracket) cuz i dont have the v6 anymore so no tps ( throttle position sensor) so im at a lost of whats goin on with it. i can take off from first but my rpms get up in 3 grand and wont shift untill i let off gas same with all gears and no od but p and n and r are fine just the normal gears and with slowin down it doesnt down shift at all i have to rachet into n to get it back into first. any ideas?!?

possible that the valve body is going out....might need a rebuild on that.

trans is shot. time for rebuild.

Take it to a trusted certified trans mechanic and let them do a road test.Post your answer and we can decide what the next step is.

Do you have the correct bracket for the TV cable and have it adjusted correctly?

Governers' stuck or sprigs broken inside
MTV up valve sticking
TV boost valve in pump
Oil filter needs replacing

Just did same rebuild...well assisted with it anyway. We had same problem. For the OD problem we simply had to adjust the kickdown cable, ours was just a bit too long. I didn't work with the downshift issue but if I remember correctly he had to adjust the TV cable to fix that problem.