Trans shop and they looked at it and told me the unit needs to be serviced

I was on the freeway (65-67mph), changed lanes & hit an uneven section of the road, it was a filled crack, maybe a 1-2” lip, the truck started shaking violently. I thought I was losing a wheel. When I started to slow down, it quit. About 10 miles later it did it again, on another small bump in the road. It was shaking so bad that the cars behind me started backing off. I pulled over and eyeballed everything & it all looked good. About 10 miles later I arrived at my house, I parked it for about an hour & when I came back out there a small puddle of tranny fluid underneath, coming from the front of the bell housing. I thought maybe the front seal. Prior to this, it had never leaked a drop on my drive way. I took it to the tranny shop and they looked at it and told me the unit needs to be serviced Thanks in advance! B