Dorman 521-218 Suspension Control Arm and Ball Joint Assembly - Rear Right Upper Rearward

Durable Suspension Control Arm and Ball Joint Assembly

The Dorman 521-218 suspension control arm and ball joint assembly is engineered for reliable performance in BMW 525i, 528i, 530i, 540i, and M5 models. Designed with pre-greased components and included bushings, this assembly ensures smooth suspension operation and long-lasting durability.

• Pre-greased for immediate use and reduced maintenance
• Includes rubber bushings and mounting hardware for a complete installation
• Threaded ball joint stud with a 14 mm thread diameter
• Constructed from durable steel with a black finish
• Designed for light suspension grade applications
• Pressed attachment type with one mounting hole (12.3 mm diameter)
• Control arm dimensions: maximum width 288.5 mm, maximum length 237 mm
• Ball joint installed and included for convenience

Product Details and Specifications

This Dorman suspension control arm and ball joint assembly (part number 521-218) is crafted from forged and cast steel to provide strength and stability for BMW vehicles including the 525i, 528i, 530i, 540i, and M5. The assembly comes pre-greased, eliminating the need for initial lubrication and helping to extend the lifespan of the ball joint. Rubber bushings are included to absorb vibrations and reduce noise, contributing to a smoother ride. The control arm features a single mounting hole with a diameter of 12.3 mm and a threaded ball joint stud, ensuring secure attachment and compatibility with factory suspension components.

Compatible BMW Models and Applications

This suspension control arm and ball joint assembly is compatible with the following BMW models:

• BMW 525i
• BMW 528i
• BMW 530i
• BMW 540i
• BMW M5

It is designed for light suspension grade use, making it suitable for standard driving conditions and daily use.

Common Suspension Issues Addressed

• Worn or damaged control arm bushings causing excessive play or noise
• Ball joint wear leading to steering instability or uneven tire wear
• Corroded or weakened control arm compromising suspension integrity
• Loose or missing mounting hardware affecting suspension alignment
• Vibration and harshness due to deteriorated suspension components

Installation Notes and Tips

Installation of the Dorman 521-218 control arm assembly requires basic suspension knowledge and tools. Since the part comes pre-greased and includes bushings and mounting hardware, it simplifies the replacement process. Ensure the vehicle is securely lifted and supported before removal of the old control arm. Verify torque specifications for mounting bolts and ball joint stud to maintain proper suspension geometry. This assembly is not adjustable, so alignment should be checked and corrected after installation.

Quality Assurance and Warranty

Dorman suspension components are manufactured to meet or exceed OEM standards for fit, form, and function. The 521-218 control arm and ball joint assembly undergoes rigorous quality checks to ensure durability and performance. While specific warranty details may vary, Dorman typically offers a limited warranty covering defects in materials and workmanship. Refer to the product documentation for exact warranty terms.