Greenbrier Companies (GBX Quick QuoteGBX - Free Report) is looking like an interesting pick from a technical perspective, as the company reached a key level of support. Recently, GBX crossed above the 20-day moving average, suggesting a short-term bullish trend.

The 20-day simple moving average is a well-liked trading tool because it provides a look back at a stock's price over a 20-day period. Additionally, short-term traders find this SMA very beneficial, as it smooths out short-term price trends and shows more trend reversal signals than longer-term moving averages.

The 20-day moving average can show signals that are similar to other SMAs as well. If a stock's price is moving above the 20-day, the trend is considered positive. When the price falls below the moving average, it can signal a downward trend.

GBX has rallied 18.4% over the past four weeks, and the company is a Zacks Rank #1 (Strong Buy) at the moment. This combination suggests GBX could be on the verge of another move higher.

Once investors consider GBX's positive earnings estimate revisions, the bullish case only solidifies. No earnings estimate has been lowered in the past two months, compared to 1 raised estimates, for the current fiscal year, and the consensus estimate has increased as well.

Investors may want to watch GBX for more gains in the near future given the company's key technical level and positive earnings estimate revisions.