Mechanical improvements start with an electronic limited-slip differential in the rear that can shift power left or right depending on which tire has traction. This should be a boon for slippery or rocky trails, and it will get extra help from the chunkier all-terrain tires and stiffer shocks fitted to the FX4. Those tires are mounted to 18-inch aluminum wheels specific to the trim level. The FX4 also gets a number of skid plates to protect vulnerable parts underneath the Expedition. There's also a "sand shield" to prevent sand and dirt from packing up the intercoolers and keeping air from flowing over them. The FX4 comes with the standard 375-horsepower EcoBoost V6 fitted to other Expeditions.
The FX4 trim isn't all mechanical upgrades, though. It also comes with a couple of subtle FX4 badges around the exterior. Some unique running boards are also fitted. Inside, rubber floor liners help keep the dirt from getting down into carpeting. Ford hasn't released pricing for the FX4 yet, but the SUV will be available this fall.