The overall ratings of three Machinery stocks are down on Portfolio Grader this week. Each of these rates a “D” (“sell”) or “F” overall (“strong sell”).

Altra (NASDAQ:AIMC) is on the decline this week, earning a D (“sell”) after receiving a C (“hold”) last week. Altra designs, produces, and markets a range of mechanical power transmission and motion control products worldwide. For a full analysis of AIMC stock, visit Portfolio Grader.

Meritor Inc. (NYSE:MTOR) earns an F (“strong sell”) this week, moving down from last week’s grade of D (“sell”). Meritor is a global supplier of drivetrain, mobility, braking and aftermarket solutions for commercial vehicle and industrial markets. In Earnings Growth, Earnings Revisions, Earnings Surprise, and Sales Growth the stock gets F’s. For more information, get Portfolio Grader’s complete analysis of MTOR stock.

Gardner Denver (NYSE:GDI) earns a D this week, falling from last week’s grade of C. Gardner Denver manufactures stationary air compressors and blowers for industrial applications. The stock also gets an F in Sales Growth. The stock price has fallen 5.9% over the past month, worse than the 3.1% increase the S&P 500 has seen over the same period of time. To get an in-depth look at GDI, get Portfolio Grader’s complete analysis of GDI stock.

Louis Navellier’s proprietary Portfolio Grader stock ranking system assesses roughly 5,000 companies every week based on a number of fundamental and quantitative measures. Stocks are given a letter grade based on their results — with A being “strong buy,” and F being “strong sell.” Explore the tool here.