What are prtal axle so, and why are they so cool? That's a great question that many an off-road enthusiast has had and many have answered for themselves. Let us bypass that step and show you what makes portal axles so darn cool for off-roading. Simply put, portal axles use a series of gears and a housing mounted on the axle ends or control arms next to the wheel to increase ground clearance under the axle. That raises the centerline of the axle and axle tubes or control arms, raises the differential relative to the wheel mounting surface, and pushes the wheels down relative to the differential and axle tubes or control arms. It's like free ground clearance at what is usually the vehicle's lowest point. And, as you know if you've spent time on the trail, the lowest fixed point on your vehicle is usually what stops your 4x4 from moving forward when you get stuck. Portal axles are a cool, although somewhat complex answer to a simple problem that we have all had off-road. The effect results in the same benefits as running a much larger tire without many of the complications that larger tires would add.