Delphi TC4390 Suspension Control Arm and Ball Joint Assembly - Front Right Lower Rearward

OE-Style Front Right Lower Rearward Control Arm

Delphi TC4390 is a suspension control arm and ball joint assembly for the front right lower rearward position. It is built with an aluminum control arm, pre-greased ball joint, included bushings, and a dust boot to support precise front suspension service on select BMW applications.

Key Features

• Part number: TC4390
• Front right lower rearward suspension control arm and ball joint assembly
• Aluminum control arm construction with casting/forged design
• Pre-greased, non-greaseable ball joint
• Ball joint, bushings, dust boot, mounting hardware, and locking nut included
• Black rubber bushings and chloroprene rubber dust boot
• Clockwise (right) thread direction
• Standard replacement grade

Detailed Description

Delphi TC4390 is engineered for the front right lower rearward suspension position on select BMW 330e, 330i, 430i, and M440i models. Delphi applies OE-focused dimensional and material analysis to help match the original part’s fit and function, while the assembly is tested across extreme temperature and salt-spray exposure conditions to verify durability in demanding road environments. The result is a direct replacement control arm assembly for BMW 330i xDrive, 430i xDrive, and related rearward front suspension applications.

This part cross-references Mevotech Supreme CMS101649 and Suspensia X05CJ1126 for the same application. Part number TC4390 is also associated with OE references 31 10 6 878 594, 31 10 6 888 856, 31 10 6 898 072, and 1028376.

What It Helps Address

• Front-end clunking or looseness from a worn control arm assembly
• Uneven tire wear caused by suspension geometry issues
• Steering wander or reduced directional stability
• Excess play from a worn ball joint or deteriorated bushings
• Noise over bumps from a damaged lower rearward arm

Installation Notes and Tips

Fits 2019-2024 BMW 330i, front right lower rearward. Fits 2020-2024 BMW 330i xDrive, front right lower rearward. Fits 2021-2024 BMW 330e, front right lower rearward. Fits 2021-2024 BMW 330e xDrive, front right lower rearward. Fits 2021-2024 BMW 430i, front right lower rearward. Fits 2022-2024 BMW 430i Gran Coupe, front right lower rearward. Fits 2021-2024 BMW 430i xDrive, front right lower rearward. Fits 2023-2024 BMW 430i xDrive Gran Coupe, front right lower rearward. Fits 2021-2024 BMW M440i, front right lower rearward. Fits 2022-2024 BMW M440i Gran Coupe, front right lower rearward. Fits 2021-2024 BMW M440i xDrive, front right lower rearward. Fits 2022-2024 BMW M440i xDrive Gran Coupe, front right lower rearward.

Confirm the front right lower rearward position before installation and inspect adjacent suspension components for wear. Because this assembly is pre-greased and not greaseable, no service fitting is provided. A professional alignment is recommended after replacement to restore proper suspension geometry.

Quality Assurance

Delphi uses OE-based engineering, dimensional checks, and material analysis to support fit consistency between original and aftermarket applications. The part is also subjected to temperature and corrosion testing to help verify durability in service.