Suspension Arms: Complete Guide to All Types and How to Buy Online

The suspension arm (also known as a control arm or wishbone) is a critical component of your vehicle’s suspension system. It connects the wheel hub to the chassis, allowing for controlled up-and-down movement while maintaining wheel alignment and stability.

Main Types of Suspension Arms

1. Lower Control Arm

This is the most common type of suspension arm. It connects the chassis to the lower part of the wheel hub and bears the brunt of the forces from the road. Most front-wheel drive vehicles use a single lower control arm per wheel.

2. Upper Control Arm

Found in double-wishbone suspension setups, the upper control arm complements the lower arm. It helps control camber angles and improves vehicle handling, particularly on uneven surfaces or during cornering.

3. Wishbone (A-Arm)

This type has two mounting points on the chassis and one on the wheel hub, forming a triangle or "A" shape. It can be used as a lower or upper arm and is common in both front and rear suspensions of various vehicles.

4. Multi-Link Arm

Used in more advanced suspension systems, multi-link setups consist of three or more arms per wheel. These offer superior handling, comfort, and fine-tuning but are more complex and expensive to replace.

5. Trailing Arm

This suspension arm runs longitudinally along the vehicle and connects the axle or wheel hub to the chassis. Common in rear suspensions, especially in older vehicles or light commercial vans.

6. Radius Rod (or Torque Arm)

Used to control longitudinal wheel motion and absorb torque, especially in high-performance or rear-wheel-drive vehicles. It’s often used in conjunction with other suspension arms.

Functions of Suspension Arms

• Maintain wheel alignment and contact with the road
• Absorb shocks and vibrations from the road surface
• Allow smooth vertical wheel movement
• Support safe steering and handling

Common Symptoms of Suspension Arm Failure

• Clunking or knocking noise while driving over bumps
• Uneven tyre wear
• Poor handling or wandering steering
• Visible damage or rust on the control arm or bushings
• Steering wheel vibration

When to Replace a Suspension Arm

Suspension arms can last 100,000 km or more, but factors like potholes, off-road driving, and accidents can shorten their lifespan. If bushings or ball joints are worn, the entire arm is often replaced to ensure safety and proper alignment.

Buying Suspension Arms Online

When purchasing a replacement suspension arm, make sure to match the following:

• Vehicle make, model, and year
• Front or rear placement
• Left or right side
• Arm type (lower, upper, wishbone, etc.)
• OEM or high-quality aftermarket part

Looking for reliable suspension arms? Our online store offers a wide range of OEM and aftermarket suspension arms for all major vehicle brands with fast delivery and competitive pricing.

Click here to browse Suspension Arms at AZ Motor Factors