Any ideas? We think it is the transmission - but are not sure....

What is your question?

We dropped the pan, found no metal shavings, did this because three times, following a slow down and stop and then a lightly accelerated pull forward, it went, but very slowly, like it was not engaging. Once I put it in reverse and it backed right up and then put it in drive and it took right off. The other two times I was pulling up to a gas pump, slowed to a stop and then went to pull more forward and it did the same thing, but then both times took right off and I haven't had a problem with it since....any deas? Fluid was good when checked as well.