Dorman 42171 Headlight Adjusting Screw

Headlight Adjusting Screw for Sealed Beam Lamps

This Dorman headlight adjusting screw is a specific-fit replacement for vehicles using sealed beam headlight assemblies. Built from metal and plastic materials, it is made to match the original part’s fit and function for dependable headlamp aiming.

Compatible with classic Ford, Lincoln, and Mercury applications, including the Ford Mustang, Lincoln Continental, and Mercury Cougar, this Dorman 42171 replacement helps restore proper headlight adjustment on the specified vehicles.

Key Features

• Specific-fit headlight adjusting screw for selected vehicles
• Designed for sealed beam headlight systems
• Metal and plastic construction
• Adjustable design for headlamp alignment
• Screw-on attachment method
• Direct replacement for Dorman 42171
• Cross-references D1TZ13032B and 421712 for the same application

Product Details

Dorman 42171 is engineered as a replacement headlight adjusting screw that follows the original fit and function on listed applications. It is used to secure and fine-tune sealed beam headlight aim, helping maintain correct beam placement after service, wear, or damaged hardware. This part is listed for 1966-1980 vehicles, including Ford Mustang, Ford Pinto, Ford LTD, Ford Thunderbird, Lincoln Continental, Lincoln Versailles, Mercury Cougar, Mercury Monarch, Mercury Bobcat, Mercury Zephyr, and Ford Fairmont.

Common Issues This Part Can Help Solve

• Broken or missing headlight adjustment hardware
• Loose headlamp aim on sealed beam assemblies
• Difficulty setting proper headlight alignment
• Worn threads or damaged screw-on adjusters
• Restoration needs on classic Ford, Lincoln, and Mercury vehicles

Installation Notes and Tips

Install this screw-on adjuster on the specified sealed beam headlight setup and verify that the headlamp housing, clips, and adjustment points are in good condition before final alignment. Because installation hardware is not included, reuse or source the required clips as needed. Confirm vehicle-specific fitment by year, make, and model before ordering.

Quality Assurance

This Dorman replacement is built to match original part fit and function using quality materials for reliable performance on the listed applications.