This week, four auto parts stocks are improving their overall ratings on Portfolio Grader. Each of these stocks is rated an “A” (“strong buy”) or “B” overall (“buy”).

BorgWarner (BWA) is progressing from last week’s rating of B (“buy”) as the company improves to an A (“strong buy”) this week. BorgWarner is a supplier of highly engineered systems and components, mainly for powertrain applications. In Portfolio Grader’s specific subcategory of Equity, BWA also gets an A. For more information, get Portfolio Grader’s complete analysis of BWA stock.

This week, Dorman Products, Inc.’s (DORM) ratings are up from a B last week to an A. Dorman Products supplies automotive replacement parts, fasteners, and service line products primarily for the automotive aftermarket. For more information, get Portfolio Grader’s complete analysis of DORM stock.

China Automotive Systems, Inc.’s (CAAS) grade is moving up to a B (“buy”) this week from last week’s C (“hold”). China Automotive System designs, markets, and sells custom-designed stained glass and leaded glass artifacts. For more information, get Portfolio Grader’s complete analysis of CAAS stock.

Federal-Mogul Corporation (FDML) shows solid improvement this week. The company’s rating rises from a C to a B. Federal-Mogul supplies products, services and solutions to automotive, light commercial, heavy-duty truck, off-highway, agricultural, marine, rail, and industrial markets. For more information, get Portfolio Grader’s complete analysis of FDML 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.