Thanks guys! So my brain somewhat cleared this morning and I remembered, earlier this week I parked overnight and then some at my cabin with it pointed uphill, pretty good slope and a load of bricks in back. Since I haven't noticed this before, I'm thinking that may have caused it, along with perhaps a worn seal. So I'm going to order the stuff to fix it, keep a close eye on the trans level and not be in a rush to fix it.