Levin points to several realistic advantages of such an alliance. GM and Toyota already have a cordial relationship. Toyota purchasing 15- to 20-percent stake of GM interest would be inexpensive for the world's second largest automaker and small enough so that it wouldn't be responsible for GM's legacy costs or attract anti-trust interest. More importantly, such a purchase would block an alliance with Nissan/Renault.
Levin goes on to discuss further advantages for both automakers, but we have a hard enough time imagining an alliance between GM and Nissan/Renault. Our brains hurt trying to imagine the mega corporation that would be comprised of GM and Toyota.
Toyota buys GM and other improbables