I have a 2000 5.4L Exp. with 103K on it. The last two months I have noticed that when the tranny downshifts from 2nd gear to first, there is a stall and then a clunk. Lately the clunking is starting to happen on 3rd to 2nd gear downshift, but only when I accelerate somewhat fast then let off, the rpms stay at about 3k and then they drop down along with the clunk noise.

Had the tranny serviced/flushed but made no difference. Seems to be worse when its cold outside.

Does this sound like a bad tranny?

Thanks