The automotive industry may be a cyclical business, but few could have foreseen the mind-blowing events of 2018. A titan of the industry suddenly died. Another is locked in a Japanese prison. The U.S. president is threatening the largest U.S. automaker for cutting thousands of jobs. And then there is Tesla CEO Elon Musk, apparently smoking pot on a podcast and tussling with federal securities regulators. Interest rates are rising and sales are falling after years of record and near-record numbers. Automakers have been relying on profits from more expensive trucks and SUVs to keep finances healthy as they battle rising material costs and try to position themselves for a rapidly changing transportation industry. "The CEO issues are huge," said Rebecca Lindland, an analyst at Cox Automotive. Questions swirl around Ford CEO Jim Hackett's ability to steer the legendary carmaker through choppy waters, she said. The death of Fiat Chrysler and Ferrari CEO Sergio Marchionne sent shock waves through the industry as has the arrest of Renault-Nissan-Mitsubishi alliance head Carlos Ghosn. Tesla's Musk has always been controversial, but his talk about taking Tesla private and his battle with federal regulators surprised even jaded onlookers. Here's a look back at some of the auto industry's biggest stories in 2018.

The trade war

A Ford Motor Co. vehicle arrives at an inspection point before being loaded onto a cargo ship at the Port of Veracruz in Veracruz, Mexico. Susana Gonzales | Bloomberg | Getty Images

President Donald Trump made his dissatisfaction with U.S. trade agreements a cornerstone of his candidacy, and it turns out his bark has had some bite. Tariffs on imported steel and aluminum went into effect in March, raising costs across the board for automakers building cars in the U.S. Ford's Hackett said the tariffs cut out $1 billion in profits for the automaker.

Ford will stop selling cars in America and plans restructuring

Ford Motor Co. 2015 Mustangs move along the production line at the company's Flat Rock Assembly Plant in Flat Rock, Michigan. Jeff Kowalsky | Bloomberg | Getty Images

Ford is making some big moves, though perhaps not as quickly as many investors would like. Its shares have been under pressure all year, falling nearly 40 percent since January. At the end of its first quarter, the second-largest U.S. automaker said it will stop selling traditional passenger cars in the U.S. and eventually winnowed the list of expected survivors to just one sports car — the Mustang. The data are highly persuasive — Americans are ditching sedans and compact cars for SUVs, crossovers and pickup trucks. That potentially bodes well for Detroit, which has in recent history competed best in truck-based segments. Those vehicles also bring bigger profits, which Ford needs to fund both a restructuring plan and investments in new mobility businesses and technologies.

Sergio Marchionne dies

Chrysler CEO Sergio Marchionne attends a press conference at Chrysler headquarters October 1, 2009 in Auburn Hills, Michigan. Bill Pugliano | Getty Images

Fiat Chrysler CEO Sergio Marchionne died suddenly over the summer, after suffering rapidly declining health that surprised many in the industry and left questions over who would fill the large shoes he left behind. He had been the man whom many credited with rescuing once bankrupt Chrysler from oblivion. Marchionne merged the troubled U.S. automaker with the Italian Fiat Group, rehabilitated the brand and shifted the company's strategy away from traditional passenger sedans and toward SUVs and pickups. Perhaps as a testament to the new importance of SUVs and pickups was the appointment of Jeep and Ram Trucks head Mike Manley as Marchionne's successor. Manley has his work cut out for him. Fiat Chrysler shares have fallen nearly 20 percent since the beginning of the year.

First-known autonomous driving fatality

Uber Volvo SUV Source: Uber

In March, a car operated by Uber fatally struck a pedestrian in Arizona, marking what many believe to be the first-known fatality involving a car using self-driving technology. Uber suspended self-driving car testing on public roads for the next eight months. However, The New York Times reported in early December that Uber plans to put its test vehicles back on the road. Uber was not immediately available for comment to CNBC. Still, investments in self-driving cars have continued unabated. Japanese conglomerate SoftBank and Japanese automaker Honda have taken stakes in General Motors subsidiary Cruise. Alphabet subsidiary Waymo became the first company to receive a permit from California to test vehicles without a driver on public roads. In early December, Waymo said it was launching a commercial self-driving ride-share service.

Elon Musk gets sued by the US government

Elon Musk smokes marijuana with Joe Rogan during a taping of Rogan's podcast show. Source: YouTube

Elon Musk is no stranger to controversy, but he seems to have outdone himself in 2018. The Tesla CEO found himself in a battle with the Securities and Exchange Commission after he publicly said in early August that he had obtained the funds needed to take Tesla private. His tweets and blog posts on the subject coincided with a significant jump in Tesla's share price, until Musk said he was abandoning the plan weeks later. Musk settled the charges with the agency. Under the terms of the deal, Musk and Tesla each had to pay separate $20 million fines. Musk has also had to step down as chairman for a period of at least three years, and Tesla will have to appoint two new independent directors. Musk also raised some eyebrows when he appeared to smoke marijuana on the Joe Rogan podcast. However, it has not all been bad for Tesla. The electric carmaker posted a surprise profit for the third quarter, and Musk has said he expects the company to continue to be profitable going forward. Tesla has long stunned investors with often sky-high share prices, but the stock is down roughly 5 percent year to date. Garrett Nelson, an analyst at CFRA, said he expects Tesla's Model 3 to become the best-selling passenger sedan in America in 2019, despite its history of production problems.

Industry titan Carlos Ghosn is arrested

Carlos Ghosn, ousted Nissan chairman. Chesnot | Getty Images News | Getty Images

Carlos Ghosn held top roles at three automakers simultaneously and was practically a living legend in the automotive industry before he was arrested in Tokyo in November. He was indicted for allegedly underreporting income and misusing company funds while chairman and CEO of the Renault-Nissan-Mitsubishi alliance. Details were still emerging in mid-December. Many industry watchers say Ghosn has been the glue holding together a tenuous alliance between French automaker Renault and Japanese car companies Nissan and Mitsubishi. Nissan executives have been critical of Ghosn in the wake of the arrest, saying he had too much power at the company. Jefferies analyst Philippe Houchois said it is likely the automakers will have to come together in the next few months and will likely redefine their relationship. This matters because the alliance has succeeded for nearly two decades, despite vocal skepticism from much of the industry. With such uncertainty plaguing the sector and the need for expensive investments in new technologies, automakers may continue to turn to alliances and partnerships to ensure their survival.

GM announces thousands of job cuts

GM Oshawa Car Assembly Plant. Vince Talotta | Toronto Star | Getty Images

No. 1 U.S. automaker General Motors said in late November that it will cut up to 14,000 jobs in North America, including both salaried and hourly workers. Somewhat like Ford, GM is trying to improve its efficiency and profitability to better prepare it for a changing future. It plans to cut production at several factories making slow-selling sedans. GM shares have fallen 21 percent year to date. Labor leaders and lawmakers in the affected regions have been critical of the decision, as has Trump. GM said in early December that some factory workers will be transferred to other facilities.

Looking to 2019

President Donald Trump talks with auto industry leaders, including General Motors CEO Mary Barra (L) and United Auto Workers (UAW) President Dennis Williams (R) at the American Center for Mobility in Ypsilanti Township, Michigan, U.S. March 15, 2017. Jonathan Ernst | Reuters