Most enclosed car transport carriers have 2 loading methods that both work well for the lowered vehicle or vehicles that have ground effects.
The 1st type of enclosed auto transport carrier loading has a lift gate that sits flat on the ground and your vehicle is driven onto it. Then the lift gate is lifted (like an elevator) to the hight of the transport truck and your car is driven into the car carrier safely.
The 2nd type of enclosed car shipping carrier loading is when your car is driven up the metal trailer track ramps. Since these are enclosed transport trucks the drivers usually come prepared to handle all types of vehicle. With the help of add on ramps they get the job done. What these add on ramps do is simple add on additional peace of ramp that usually starts paper flat with the pavement and extends to were the original ramp sits on the pavement.
Both loading methods work well and if done correctally will result in your vehicle getting aboard the transport carrier safely. Plus if you are there at the pick up location you can keep a close eye

on the truck driver as he loads your vehicle and give assistance if needed. But remember the truck drivers do this all day long so they are pretty good at loading and unloading vehicles off there carriers.