Railcar manufacturer Greenbrier Cos (NYSE: GBX) pre-announced its quarterly results and said it received orders for 4,500 new cars during the period. Investors are excited, sending Greenbrier shares up more than 10% for the week, according to data provided by S&P Global Market Intelligence. Greenbrier isn't expected to release results from its fiscal second quarter ended Feb. 28 until April, but the company this week provided an update that gave investors reasons to cheer.