Dorman 521-939 Radius Arm - Front Left

Durable Radius Arm for Ford Bronco and F-150 Suspension

The Dorman 521-939 radius arm is engineered to provide reliable suspension support for Ford Bronco and F-150 models. Constructed from sturdy steel with a black finish, this radius arm is designed to maintain proper wheel alignment and suspension geometry.

• Made from high-quality steel with a 6 mm wall thickness for strength
• Measures 641 mm in length with a maximum width of 146 mm and minimum width of 22 mm
• Features fine thread type bolts with a 19.5 mm diameter and 30 mm length
• Includes rubber bushing material (bushings not included)
• Standard replacement suspension grade type for dependable performance

Product Details and Specifications

The Dorman 521-939 radius arm is designed specifically for suspension systems on Ford Bronco and F-150 vehicles. Its steel construction ensures durability under typical driving conditions, while the black coating helps resist corrosion. The radius arm’s dimensions—641 mm length and 146 mm maximum width—are engineered to match factory specifications, ensuring proper fit and function. Although bushings and mounting hardware are not included, the arm is compatible with standard rubber bushings and fine-thread bolts with a 19.5 mm diameter. This part serves as a standard replacement component, maintaining the suspension geometry necessary for vehicle stability and handling.

Common Applications and Problem Resolution

• Restores proper wheel alignment and suspension geometry
• Replaces worn or damaged radius arms causing uneven tire wear
• Addresses suspension noise or looseness related to faulty radius arms
• Improves vehicle handling and ride quality by stabilizing suspension components
• Supports suspension integrity after collision or off-road damage

Installation Notes and Tips

Installation of the Dorman 521-939 radius arm requires removal of the old radius arm and proper alignment of the new part. Since bushings and mounting hardware are not included, ensure compatible rubber bushings and fine-thread bolts (19.5 mm diameter) are available before installation. Torque specifications should follow Ford’s factory guidelines to maintain suspension performance and safety. It is recommended to have a professional alignment performed after installation to ensure optimal handling.

Quality Assurance and Warranty

Dorman radius arms are manufactured to meet or exceed OEM standards for fit, form, and function. The 521-939 part undergoes quality inspections to ensure durability and reliability in suspension applications. This radius arm is backed by Dorman’s limited warranty, providing coverage against defects in material and workmanship under normal use.