Can we make Gasoline from used motor oil?

Possible but very expensive and economically foolish. The best use is for re-refining into more lube oil, followed by combustion in such equipment as cement kilns or very large diesel engines with coke bottle-size injectors.

In the artic it’s illegal to dispose of used oil. There is a manufacturer who makes special space heaters that can be fired with used oil. A really neat solution but some air headed environmentalist will no doubt claim that this causes air pollution and the oil should be shipped back to the Lower Forty Eight for “proper disposal”. Never mind all the energy needed (with additional greenhouse gasses) to bring the stuff back stateside.

When oil companies have a large amount of used oil on their hands, They can re-refines it (if they have a re-refinery), they can either burn it in the refinery furnaces, or dump it back ito the crude oil feedstock, where it will end up as either a heavy bunker fuel oil or, if the overall feedstock is suitable for making lube oil, as new lube stock. Under no circumstamnces will this oil be “cracked” or hydrogenated into gasoline.