Moog RK621000 Suspension Control Arm and Ball Joint Assembly - Front Left Upper Rearward

OE-Style Front Left Upper Rearward Control Arm

The Moog RK621000 is a suspension control arm and ball joint assembly for select Audi applications. It is built with forged aluminum for structural strength and corrosion protection, and it comes pre-greased with bushings and mounting hardware included.

Compatible with Audi A4, A4 Quattro, A5, A5 Quattro, S4, S5, RS5, Q5, and SQ5 front left upper rearward suspension positions, this assembly supports precise front-end suspension service on vehicles that use a press-in ball joint and pinch-style stud connection.

• Forged aluminum control arm construction
• Pre-greased for service-ready installation
• Rubber bushings included
• Press-in ball joint mounting type
• Pinch-style ball joint stud type
• Mounting hardware included
• Gray finish with corrosion protection focus
• Non-adjustable OE-style replacement design

Detailed Product Overview

Moog RK621000 is engineered as a direct replacement suspension control arm and ball joint assembly for the front left upper rearward position. It is a fitment-based solution for 2008-2017 Audi A5 Quattro, 2008-2017 Audi S5, 2009-2016 Audi A4, 2009-2016 Audi A4 Quattro, 2013-2016 Audi Q5, 2010-2016 Audi S4, 2014-2016 Audi SQ5, 2013-2015 Audi RS5, 2012-2014 Audi A5, and 2010 Audi A5. The Moog RK621000 uses forged aluminum and rubber bushings to restore suspension geometry and help maintain stable steering response.

This part cross-references Delphi TC2335 and Dorman - OE Solutions 521-253 for the same application.

Common Issues This Part Can Address

• Front suspension looseness or play at the upper rearward control arm
• Clunking or knocking from the front left suspension area
• Uneven tire wear caused by worn control arm bushings or ball joint wear
• Steering wander or reduced front-end stability
• Suspension noise during braking, turning, or road impacts

Installation Notes and Tips

Verify the front left upper rearward position before installation and confirm vehicle-specific fitment by year, make, and model. This assembly uses a press-in ball joint with a pinch-style stud, so proper suspension service procedures and alignment checks are recommended after replacement. The unit is pre-greased and includes bushings and mounting hardware, which helps streamline installation on Audi A4, A4 Quattro, A5, A5 Quattro, S4, S5, RS5, Q5, and SQ5 applications.

Quality Assurance

Moog premium control arms are engineered for structural strength and corrosion protection for foreign and domestic nameplates. The RK621000 is built to OE-style standards for suspension service and replacement consistency.