This week, the ratings of 4 Machinery stocks on Portfolio Grader are down. Each of these rates a “D” (“sell”) or “F” overall (“strong sell”).

This week, Westinghouse Air Brake Technologies Corporation (WAB) drops from a C to a D rating. Westinghouse Air Brake Technologies Corporation is a provider of value-added, technology-based products and services for the global rail industry. For more information, get Portfolio Grader’s complete analysis of WAB stock.

Caterpillar Inc. (CAT) is having a tough week. The company’s rating falls from a D to a F. Caterpillar Inc. provides construction and mining equipment, diesel and natural gas engines, and industrial gas turbines. The company also gets F’s in sales growth. For more information, get Portfolio Grader’s complete analysis of CAT stock.

Graham Corporation’s (GHM) rating weakens this week, dropping to a F versus last week’s D. Graham Corporation designs and builds vacuum and heat transfer equipment for process industries around the world. The company also gets F’s in sales growth and earnings momentum. For more information, get Portfolio Grader’s complete analysis of GHM stock.

Accuride Corporation (ACW) slips from a D to a F this week. Accuride Corporation engages in designing, manufacturing, marketing, and supplying commercial vehicle components in North America. The company also gets F’s in sales growth, operating margin growth, and earnings revisions. For more information, get Portfolio Grader’s complete analysis of ACW 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.