Frickin fiat!!!

Tried to go pick up wife at airport. Oncoming ambulance on Hwy 20 I went from 55 mph to a near stop onto shoulder of road. This caused the vehicle to shudder, didn't quite stall but transmission wouldn't get vehicle moving, kind of wound up rpms so I backed off throttle, then I felt the trans shift up through all gears with the Jeep barely moving. Turned around, got my Suburban. Took Jeep back to dealership service today, fix it for real this time please. I asked them what the codes were the first time, they said low oil and something about manifold vacuum. Wonder which code it was this time, hopefully not a catastrophic internal engine failure, I"ve read a couple of horror stories.