Tesla overtakes GM to become most valuable U.S. auto maker

Tesla Inc. on Monday became the largest U.S. auto maker by market value, Tesla stock climbed as much as 3.7 percent in early Monday trading, boosting its market capitalization to $51 billion. GM is valued at $50.30 billion. Tesla announced that it produced 25,418 electric cars in this year’s first quarter. The company, run by Elon Musk, will start producing its new, more affordable sedan, the Model 3 later this year. The Model 3 is expected to transform the niche electric car company into a mass-market manufacturer.