Is the global Automobile Industry changing from an oligopoly to monopolistic competition? The current situation is the automobile industry is an oligopoly as there are few big firms and massive barriers to entry due to cost.

However, The industry seems like it is changing to a monopolist competition structure as new firms join the industry (Apple, Google). This is as a result of bigger differentiation’s in cars product (due to software)
The automotive industry is being disrupted by new trends such as electric vehicles and self-driving cars. These, still, represent a minor part of the market. 

So the answer would be no, for the moment besides media attention, there weren't gigantic shifts in the industry as to have monopolies. Looking at the last years data it seems to remain an oligopoly with 4 very large manufacturers.

If you need further info this is usually not free - look for the automotive industry in business databases such as IBIS world, or get a report from a consulting firm such as this one.