The grades of four auto parts stocks are better this week, according to the Portfolio Grader database. Every one of these stocks has an “A” (“strong buy”) or “B” overall (“buy”) rating.

This week, Dorman Products, Inc. (DORM) is making solid headway. The company’s rating improves to an A (“strong buy”) from last week’s B (“buy”) rating. Dorman Products supplies automotive replacement parts, fasteners, and service line products primarily for the automotive aftermarket. In Portfolio Grader’s specific subcategory of Equity, DORM also gets an A. For more information, get Portfolio Grader’s complete analysis of DORM stock.

China Automotive Systems, Inc. (CAAS) is making progress this week as its rating of C (“hold”) from last week increases to a B (“buy”) rating this week. 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.

BorgWarner (BWA) shows solid improvement this week. The company’s rating rises from a B to an A. BorgWarner is a supplier of highly engineered systems and components, mainly for powertrain applications. For more information, get Portfolio Grader’s complete analysis of BWA stock.

This week, Federal-Mogul Holdings Corp (FDML) pushes up from a C to a B rating. 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.