Note:
In my mind, the tractor and trailer is not wrecked. It has about 25 people in it.
The symptoms of its breakdown is they were drinking and the engine was running rough and when they pulled over, the engine went "CLUNK!: and died. That means one of two things - 1) Bad fuel or 2) Engine seize. Or three - both.
Engine seize can be fixed with the midas touch. Bad fuel needs to be flushed out and drained. Even though the fuel in the tanks maybe bad, it can be used as the fuel/water separator will do its thing now that it is drained. This device on all diesel vehicles, lasts about 10,000 miles and need to drained at that time. It is this job that needs the most work as the stuff in the engine needs to be drained. This system runs on a vacuum in separating water from fuel and the water is put in a small tank. When that tank fills it needs to be drained out or it floods the engine with fuel and water mix and shuts down combustion. So at this point the tank and engine fuel pipes needs to be drained. The job is simple but takes time to do.
Fuel/Water Separator (they come in many shaps and sizes):
Drain valve, to remove the water it catches - every 10K miles)
The teleportation is to be done where it wont be witnessed by others. Even if the spirits use a different technique, witnesses will see a truck disappear and then reappear with a tractor trailer. That is why Fernando wants to drive out of town where this action wont be seen. Also on the other end, seeing that they appear a mile away, they can survey the scene as they approach the tractor and get ready to work. In short Fernando does not want any witnesses who can connect them to any spirits - good or bad. But those riding with us will know because it is only fair for them to know. Also, in driving the tractor trailer that distance will test the repair and see if more is needed. When they drive into town, no one will be wiser as to what happened. All they see is Karl's SUV leading a tractor trailer into the parking lot.
Any wrecks on the side of the road would have been minded for their parts and metal by this group while they wait for their 'leaders' to return with help.