The Dow Jones Industrial Average (DJINDICES:^DJI) was up and down today before surging by more than 50 points just before 3 p.m. after Federal Reserve Chairman Ben Bernanke and other Fed officials offered public comments on the economy and stimulus policy. With that in mind, take any knee-jerk market reactions and volatility with a grain of salt.

In other news, it was a big day for many large industrial companies. Here's what you need to know.

Inside the Dow, General Electric (NYSE:GE) traded flat after pieces of positive and negative news hit the feeds. On the bright side, the Department of Defense awarded a $572.5 million defense contract to GE yesterday. The contract calls for General Electric to repair and replace components for 17 of its F414 afterburning turbofan engines over the next three years. The engines are used to power Navy F/A-18E and –F fighter jets, as well as EA-18G electronic warfare aircraft.

On the down side, General Electric was downgraded to perform from outperform by Oppenheimer analyst Christopher Glynn. He noted that the company is already fairly valued and that "2014-15 represents a transitional period." While this is true, the company is striving to grow its industrial business over its financial service -- GE Capital contributed 47% of GE's operating earnings in its third quarter. GE's goal is to grow its industrial business to 70% of operating earnings, and the faster it can do so the faster analysts will grow to appreciate the stock's potential.

Outside of the Dow, 3D Systems (NYSE:DDD) is moving more than 2% higher after announcing today it would acquire Gentle Giant Studios, a leading provider of 3-D modeling for the entertainment and toy industry. 3D Systems will look to instantly leverage the acquired company and use its vast library of digital content, which includes licensed 3-D characters from Marvel, Disney, AMC's The Walking Dead, Avatar, Harry Potter, and Star Wars.

"Gentle Giant Studios catapults 3DS's consumer platform forward with highly curated, licensed characters, content publishing know-how and first-mover experience for the benefit of leading toy companies, movie studios and their merchandising divisions," 3D Systems President and CEO Avi Reichental said in a press release.

Friday also brings big news from the automotive industry, as all companies will be reporting December sales figures throughout the day.

Ford's F-Series sales surged while the Silverado's plunged. Photo credit: Ford

December is historically the industry's best month for multiple reasons. The holidays bring a surge of consumer activity, as well as with larger incentives and discounts to drive sales. Businesses tend to purchase year-end equipment if deemed in their best interest due to tax write-off purposes. However, in 2013 some sales may have been pulled into November as Black Friday deals seem to begin earlier and earlier each year. For that reason, in combination with winter storms toward the end of the month, sales seem to have come in slightly lower than expected.

Looking at the two largest domestic automakers, Ford (NYSE:F) posted a sales increase of 2% while General Motors' (NYSE:GM) sales declined 6% -- GM is currently trading more than 3% lower. While General Motors' sales definitely disappointed compared to last year, its total deliveries of 230,157 for December topped Ford's 218,058 mark. However, there's one key factor that changes the tide for investors.

Investors who follow the automotive industry closely understand that full-size pickups drive the majority of profits for all domestic automakers. Full-size pickups carry higher transaction prices, as well as margins -- they are the most important vehicles for Ford, GM, and Chrysler, hands down.

Typically when one company unleashes a fresh design, sales surge, incentives decrease, and profits rise. Unfortunately the first factor I mentioned didn't happen for General Motors in December.

Fresh designs of GM's most important two vehicles, the Silverado and Sierra, posted sales declines of 16% and 4.6%, respectively -- a big disappointment. Ford's F-Series and Chrysler's Ram Truck brand were up 8.4% and 17%, respectively. Over the next few days incentive spending for the month of December will be finalized, and it will be important for investors to know if Ford and Chrysler had to significantly raise their incentives to take market share -- albeit less profitably -- or if GM's full-size pickup sales plunged for other reasons.