Excuse me for asking, but which 4x4 cannot tow a 747?
I'm sure that even a Mahindra MM540 4x4 should be able to do it, with the right ballast weight and wide radial tires. It has more to do with the compliance of the 747 to be towed than special abilities of the 4x4 concerned.
However, if one is looking for extreme capabilities, there are tractor pull events which push man and machine to severe limits. I witnessed one in the northern outskirts of Ottawa, Ontario, Canada.
In these there is a standard load which slides up a ramp getting more and more difficult until the tractor gives up.
Tractor pulling is a competitive motorsport. Hobby vehicles and rigs are modded for extreme torque.
They drag a metal sled down a designated course. This sled has a heavy payload of lead plates.
These plates mechanically winch forward, as the sled progresses along the course.
Competitors pulling this ever-increasing load eventually lose forward speed, momentum and torque.
Winners sometimes reach the end of the course. The start to finish distance is measured to a precision of 0.01 inch.
The competitor which pulled the sled the farthest distance is declared winner. If multiple competitors reach this far, a run-off is held. Here heavier weights and/or greater distance is used to pick a winner amongst the winners.
Ram