350AT shift up/down repeatedly

[72CampSpecial]

ive searched the forums and haven't found a matching issue.. my trani shifts up/down repeatedly under light throttle (around 20 mph/sometimes around 30 mph)..Seems to be more when its cold first 5 min of driving.

Already did a fluid/filter change, swapped out the Accumulator Seal (was leaking) and the vacuum modulator (thought it was bad..but dont think it was after changing it) (and it was a lot smaller than the original??) and installed a new vacuum line from the modulator.

other vacuum lines to look at? Adjustments to make??

it shifts smooth and really good under heavy accelerations..