Dorman 520-731 Suspension Control Arm and Ball Joint Assembly - Front Left Lower

Durable Suspension Control Arm and Ball Joint Assembly for BMW Models

The Dorman 520-731 suspension control arm and ball joint assembly is engineered for reliable performance in select BMW vehicles. Designed specifically for BMW 318i, 318is, 325e, 325es, 325i, and 325is models, this assembly ensures proper suspension function and vehicle handling.

• Pre-greased ball joint for immediate use
• Press-in ball joint mounting with threaded stud
• Constructed from durable iron with a black finish
• Includes mounting hardware for straightforward installation
• Compatible with light suspension grade requirements

Product Features and Specifications

This suspension control arm and ball joint assembly from Dorman is crafted from forged and cast iron, providing strength and durability for regular driving conditions. The ball joint is pre-installed and pre-greased, eliminating the need for additional lubrication during installation. Featuring a press-in mounting type and a threaded ball joint stud with a 14 mm thread diameter, it offers secure attachment and reliable steering response. The control arm measures up to 288.5 mm in width and 237 mm in length, with a single 12.3 mm mounting hole. Although bushings are not included, the assembly comes with all necessary mounting hardware to facilitate replacement.

Compatible BMW Models and Applications

This Dorman 520-731 control arm and ball joint assembly is compatible with the following BMW models: 318i, 318is, 325e, 325es, 325i, and 325is. It is designed to meet the suspension requirements of these vehicles, particularly for light suspension grade applications. Using this assembly helps maintain proper wheel alignment and suspension geometry, contributing to vehicle stability and handling.

Common Suspension Issues Addressed

• Worn or damaged control arm causing uneven tire wear
• Loose or failing ball joint affecting steering precision
• Suspension noise due to degraded components
• Misalignment leading to poor handling and ride quality
• Corrosion or fatigue in original control arm material

Installation Notes and Tips

Installation of the Dorman 520-731 assembly requires basic suspension knowledge and tools. Since the ball joint is pre-installed and pre-greased, no additional lubrication is necessary. Ensure the mounting hole aligns correctly with the vehicle’s frame and torque all hardware to manufacturer specifications. This assembly is not adjustable, so proper fitment verification before installation is recommended. Replacement should be performed on both sides if wear is uneven to maintain balanced suspension performance.

Quality Assurance and Warranty

Dorman parts are manufactured to meet or exceed OEM standards for fit, form, and function. The 520-731 suspension control arm and ball joint assembly undergoes rigorous quality checks to ensure durability and reliability. While specific warranty details may vary, Dorman typically offers a limited warranty covering defects in material and workmanship. Consult product documentation for exact warranty terms.