Yeah, It doesn't take much water to hydrolock your truck... I've been in up to and past my headlights, but I hit the water slow & also be sure to create a bow wave in front of me, so the water in my engine bay stays low...
Couple years ago one of the guys in our club hydrolocked his truck whipping thru puddles on one of the 'fireroads' at Rausch Creek... we all blasted thru it, but he managed to hit it at such a speed/angle/stroke of bad luck, it hit the airbox, blew a hole through the airfilter. They were picking bits of airfilter out of places you'd never imagine it could get.
Since then, I avoid that urge to whip thru even the most innocent looking puddles...
Sorry to hear about your luck... hopefully you can fix it with out too much of a financial kick in the ass.