hey Matt,
I Seem to be having a similar problem on my 96 explorer 4x4 with a hard 1-2 shift, i recently replaced a B-Solenoid after geting p0756 on my code reader and that fixed the problem for about a month yesterday i was driving and accelerated hard from a stop and it began to slip. If i am light on the gas it will simply shift from 1-2 roughly.. but if i gas hard then it tends to slip.. I am thinking of replacing the transmission. any suggestions? or should i simply do the gasket as you spoke about in the above postings.