Audi Audi S4 2003-2008

Audi Audi S4 2003-2008 Suspension Specifications

Comprehensive technical specifications for the suspension system of the 2003-2008 Audi S4, including detailed information on front and rear suspension components, alignment settings, torque values, and maintenance procedures.

Updated Oct 14, 2023

Overview Specifications

Comprehensive description of the suspension specifications for the 2003-2008 Audi S4, including key features, measurements, and technical details. This section covers the front and rear suspension systems, including components such as shock absorbers, springs, control arms, and anti-roll bars.

How to Use

Use the search function to locate specific suspension components or specifications by entering keywords such as 'front suspension', 'rear shock absorber', or 'spring rate'.

Navigate through the suspension documentation by selecting the relevant section from the table of contents. Each section is organized by component type and includes detailed technical specifications.

Key Specifications

Front Spring Rate

28 N/mm

Rear Spring Rate

32 N/mm

Front Anti-Roll Bar Diameter

25 mm

Rear Anti-Roll Bar Diameter

22 mm

Wheelbase

2650 mm

Available Specifications

Front Suspension

Detailed information about the front suspension system, including the MacPherson strut design, control arms, and anti-roll bar.

MacPherson Strut Assembly

Strut type: Gas-filled monotube shock absorber
Spring rate: 28 N/mm (front)
Strut diameter: 55 mm
Bump stop length: 60 mm
Top mount bearing type: Angular contact ball bearing

Control Arms and Bushings

Upper control arm material: Aluminum forged
Lower control arm material: Steel stamped
Bushing material: Hydro rubber with Teflon coating
Bushing durometer: 70 Shore A
Control arm length: 320 mm (upper), 450 mm (lower)

Note: Ensure proper torque specifications during installation to prevent premature bushing wear.

Rear Suspension

Detailed information about the rear suspension system, including the multi-link design, shock absorbers, and anti-roll bar.

Multi-Link Suspension

Link type: Four-link independent suspension
Spring rate: 32 N/mm (rear)
Shock absorber type: Twin-tube gas-filled
Shock absorber diameter: 50 mm
Bump stop length: 55 mm

Anti-Roll Bar

Anti-roll bar diameter: 22 mm (rear)
Material: Hollow steel
Bushing material: Polyurethane
Bushing durometer: 75 Shore A
Mounting torque: 25 Nm

Note: Regularly inspect bushings for wear and replace if necessary to maintain handling performance.

Suspension Geometry

Technical details about the suspension geometry, including alignment specifications and ride height.

Alignment Specifications

Front camber: -0.5° to -1.0°
Front toe: 0.10° to 0.20° (toe-in)
Rear camber: -1.5° to -2.0°
Rear toe: 0.15° to 0.25° (toe-in)
Caster angle: 7.5° to 8.5°

Ride Height

Front ride height: 140 mm (measured from wheel center to fender)
Rear ride height: 135 mm (measured from wheel center to fender)
Ground clearance: 120 mm
Wheelbase: 2650 mm
Track width: 1540 mm (front), 1520 mm (rear)

Note: Ride height measurements are taken with the vehicle unloaded and on level ground.

Search Specifications

Search by specification name, value, or description

Component Specifications

Front Suspension

Type: Double wishbone with coil springs and gas-filled shock absorbers

Spring Rate: 32 N/mm

Shock ABSorber Travel: 120 mm

Anti Roll Bar Diameter: 22 mm

Bushings Material: Synthetic rubber with PTFE coating

Part Numbers: Shock ABSorber: 8E0 413 031
Coil Spring: 8E0 411 105
Anti Roll Bar: 8E0 411 305

Rear Suspension

Type: Trapezoidal link with coil springs and gas-filled shock absorbers

Spring Rate: 28 N/mm

Shock ABSorber Travel: 110 mm

Anti Roll Bar Diameter: 18 mm

Bushings Material: Synthetic rubber with PTFE coating

Part Numbers: Shock ABSorber: 8E0 513 031
Coil Spring: 8E0 511 105
Anti Roll Bar: 8E0 511 305

Alignment Specifications

Front Camber: -0.5° to -1.0°

Front Toe: 0.10° to 0.20°

Front Caster: 7.0° to 8.0°

Rear Camber: -1.5° to -2.0°

Rear Toe: 0.15° to 0.25°

Tolerance: ±0.2°

Shock ABSorbers

Type: Gas-filled monotube

Compression Force: 1200 N

Rebound Force: 800 N

Operating Temperature Range: -40°C to 120°C

Service Life: 100,000 miles or 10 years

Part Numbers: Front: 8E0 413 031
Rear: 8E0 513 031

Coil Springs

Material: High-strength steel with corrosion-resistant coating

Front Spring Length: 320 mm

Rear Spring Length: 300 mm

Load Capacity: Front: 1200 kg
Rear: 1000 kg

Part Numbers: Front: 8E0 411 105
Rear: 8E0 511 105

Anti Roll Bars

Material: Hollow steel with anti-corrosion coating

Front Diameter: 22 mm

Rear Diameter: 18 mm

Bushing Material: Synthetic rubber with PTFE coating

Part Numbers: Front: 8E0 411 305
Rear: 8E0 511 305

Bushings And Mounts

Front Control Arm Bushings: Synthetic rubber with PTFE coating

Rear Trapezoidal Link Bushings: Synthetic rubber with PTFE coating

Shock ABSorber Mounts: Reinforced rubber with steel inserts

Part Numbers: Front Bushings: 8E0 407 181
Rear Bushings: 8E0 507 181
Shock Mounts: 8E0 413 039

Suspension Limits

Maximum Load: Front Axle: 1200 kg
Rear Axle: 1000 kg

Maximum Speed With Load: 250 km/h

Maximum Operating Temperature: 120°C

Minimum Operating Temperature: -40°C

Diagnostic Specifications

Shock ABSorber Leak Test: No visible fluid leakage after 100,000 miles

Bushing Wear Limit: 2 mm maximum play

Spring Sag Limit: 5% of original length

Alignment Check interval: Every 15,000 miles or 12 months

Maintenance Specifications

Lubrication Points

Front control arm bushings
Rear trapezoidal link bushings
Anti-roll bar bushings

Lubrication interval: Every 30,000 miles or 24 months

Torque Specifications: Shock ABSorber Mount Nuts: 50 Nm
Control Arm Bolts: 90 Nm
Anti-Roll Bar Bracket Bolts: 25 Nm

Service Information Service

Detailed service requirements and schedules for the suspension system

15,000 miles

12 months

Inspect shock absorbers for leaks and wear
Check suspension bushings for play and wear
Verify alignment specifications

Alignment check is critical after any suspension component replacement

30,000 miles

24 months

Lubricate all suspension bushings
Inspect coil springs for sag or damage
Check anti-roll bar mounts and bushings

Use only Audi-approved lubricants for bushings

60,000 miles

48 months

Replace shock absorbers if necessary
Inspect and replace worn bushings
Verify torque on all suspension bolts

Shock absorbers should be replaced in pairs

Frequently Asked Questions

Find answers to common questions about torque specifications

What type of suspension does the 2003-2008 Audi S4 use?

The 2003-2008 Audi S4 features a four-link front suspension with an independent trapezoidal-link rear suspension. Both front and rear suspensions are equipped with coil springs and gas-filled shock absorbers, providing a balance of sporty handling and ride comfort.

What is the recommended ride height for the Audi S4 suspension?

The factory ride height for the 2003-2008 Audi S4 is approximately 150mm (5.9 inches) at the front and 145mm (5.7 inches) at the rear, measured from the center of the wheel hub to the edge of the wheel arch. Variations may occur depending on trim and optional suspension packages.

Can I lower the suspension on my Audi S4 without affecting performance?

Lowering the suspension can improve handling but may compromise ride comfort and increase wear on suspension components. If lowering, use Audi-approved lowering springs or a compatible aftermarket kit designed for the B6/B7 platform. Ensure proper alignment and damping adjustments to maintain performance and safety.

What is the torque specification for the front suspension control arm bolts?

The torque specification for the front suspension control arm bolts on the 2003-2008 Audi S4 is 70 Nm (52 lb-ft) plus an additional 90-degree turn. Always use a torque wrench and follow Audi's tightening sequence to ensure proper installation.

How often should the suspension components be inspected?

Audi recommends inspecting the suspension components every 15,000 miles or annually, whichever comes first. Pay special attention to bushings, ball joints, and shock absorbers for signs of wear or damage. Severe driving conditions may require more frequent inspections.

What is the recommended alignment specification for the Audi S4?

The factory alignment specifications for the 2003-2008 Audi S4 are as follows: Front Camber: -0°30' to -1°00', Front Toe: 0°05' to 0°15', Rear Camber: -1°30' to -2°00', Rear Toe: 0°10' to 0°20'. Always perform alignment adjustments using Audi-approved equipment and procedures.

Factory Service Resources

Access official service manuals, technical documents, and repair guides. These resources provide detailed procedures, specifications, and diagrams directly from the manufacturer.

Audi S4 Suspension Service Manual

Coming Soon

Official Audi service manual detailing suspension maintenance, repair, and alignment procedures for the 2003-2008 S4.

Suspension Component Replacement Guide

Coming Soon

Step-by-step guide for replacing common suspension components such as control arms, bushings, and shock absorbers.

Performance Suspension Upgrades

Coming Soon

Overview of Audi-approved and aftermarket suspension upgrades for improved handling and ride quality.

Alignment and Handling Optimization

Coming Soon

Technical guide to optimizing suspension alignment and handling for the 2003-2008 Audi S4.

About the Author

Expert automotive knowledge and experience

ASE

Alan Montanye

Automotive Technical Specialist

ASE Master Certified Technician with over a decade of hands-on experience in automotive repair and diagnostics.

Facebook Contact

15+ Years

Experience

500+ Guides

Guides

50+ Makes

Vehicles

1000+ Solutions

Solutions

Diagnostic

Specialized in advanced diagnostic techniques using modern scan tools and oscilloscopes.

Repair

Expert in both traditional mechanical repairs and modern vehicle systems.

Additional Expertise

Documentation

Created over 500 detailed repair guides and technical documents.

Training

Conducted technical training sessions and contributed to repair databases.

Certifications & Research

Certifications

ASE Master Technician Certification
Advanced Diagnostic Specialist
Hybrid/Electric Vehicle Systems
Performance Tuning Expert

Research & Community

Actively researches emerging technologies and contributes to automotive forums.

Legal Disclaimer

Important information about using this content

Always refer to your vehicle's service manual and take appropriate safety precautions when performing any maintenance or repairs.

General Information

The information provided on this website is for general informational purposes only. While we strive to maintain accuracy in our content, all specifications, procedures, and technical information should be verified against your vehicle's official service manual or with the manufacturer directly.

Warranty & Liability

The content on this website is provided "as is" without any representations or warranties, express or implied. We make no representations or warranties regarding the accuracy, completeness, or availability of the information.

We shall not be liable for any direct, indirect, special, or consequential damages arising from the use of information on this website.

Technical Information

All specifications, including torque values, fluid capacities, and maintenance procedures, should be verified against your vehicle's factory service manual.
Vehicle specifications and procedures may vary by model year, trim level, and region.
Always follow the manufacturer's recommended procedures and safety precautions.
Working on vehicles can be dangerous. Always take proper safety precautions and use appropriate safety equipment.
If you're unsure about any procedure, consult a qualified professional mechanic.

Intellectual Property

All content, including text, images, and specifications, is protected by copyright and other intellectual property laws. Any unauthorized use or reproduction is prohibited.