Dorman 527-257 Suspension Control Arm and Ball Joint Assembly - Front Left Upper

Dorman 527-257 Front Left Upper Control Arm

Dorman 527-257 is a direct replacement suspension control arm and ball joint assembly for select BMW applications. It is built for the front left upper position and is engineered to restore smooth ride quality, directional stability, and predictable steering response on BMW X5, X6, X7, Alpina XB7, and iX models.

Key Features

• Direct replacement for the original equipment front left upper control arm
• Pre-greased and supplied with the ball joint installed
• Aluminum control arm construction with casting/forged design
• Includes bushings and mounting hardware
• Machined ball joint mounting with pinch-style stud
• Standard replacement grade for OE-style service
• Compatible with BMW X5, X6, X7, Alpina XB7, and iX front suspension applications

Detailed Description

This Dorman 527-257 suspension control arm and ball joint assembly is built as an OE-style replacement for the front left upper suspension position. The aluminum arm uses a casting/forged construction and comes with the ball joint installed, pre-greased, and ready for service. Bushings are included, and the assembly is designed to match the original fit and function on specific BMW platforms. This part cross-references MOOG Chassis Products RK623925 for the same application.

For fitment-focused searches, this part fits 2019-2025 BMW X5, front left upper; 2020-2025 BMW X6, front left upper; 2019-2025 BMW X7, front left upper; 2021-2025 BMW Alpina XB7, front left upper; and 2022-2025 BMW iX, front left upper. If you are replacing a worn BMW X5 front left upper control arm or servicing a BMW X7 front suspension, Dorman 527-257 provides the correct OE-style layout for these applications.

What It Helps Fix

• Clunking or knocking from the front suspension
• Loose or imprecise steering feel
• Uneven tire wear caused by worn suspension joints or bushings
• Directional instability during braking or lane changes
• Excess play in the upper control arm assembly

Installation Notes

Verify the front left upper position and confirm vehicle application before installation. Inspect adjacent suspension components, alignment angles, and mounting points for wear or damage before replacing the assembly. Because the ball joint is installed and the unit is pre-greased, installation is streamlined compared with rebuilding individual components. A professional wheel alignment is recommended after suspension work.

Quality Assurance

Dorman uses an industry-leading evaluation process to help ensure proper fit, smooth ride quality, directional stability, and predictable handling characteristics. This 527-257 assembly is a standard replacement part built to restore original suspension function on the listed BMW applications.