Just be careful at any speed going through deep water. While a little different setup, about six years ago we had a crown vic in our fleet go through deep water. With newer cars and trucks the air intake for the engine goes down into the wheel well for cold air intake. Sucked a bunch of water into and blew the engine. The Sport trac rides higher, but something to think about and keep in mind.
One more thing. The gen 1 5r55e trans has a vent tube on the drivers side. If the tube is submerged and you let of the gas enough. The front pump on the trans might suck up water. Water and hot trans fluid steams and destroys, clutch and band material.