Two Generations, One Firm Pedal Solution
Whether you’re running an early B5 or a later B7 chassis Audi A4, the factory rear rubber brake hose ages the same way, softening pedal feel over time. The Wilwood 221-17415 rear flexline kit swaps in a braided stainless steel line, giving both generations a firmer, more direct pedal.
Key Features
- Direct bolt in replacement for the factory rear rubber brake hose
- Braided stainless steel construction resists expansion under hard braking
- DOT compliant for street legal use
- Improves brake pedal feel and response compared to aging rubber lines
- Corrosion resistant PTFE inner liner for long service life
- Wilwood MPN 221-17415 rear position kit
Fitment Table
| Year Range | Make | Model |
|---|---|---|
| 1996-2001 | Audi | A4 |
| 2004-2009 | Audi | A4 |
Specifications
| Detail | Value |
|---|---|
| Brand | Wilwood |
| MPN | 221-17415 |
| UPC | N/A |
| Position | Rear |
| Construction | Braided Stainless Steel, PTFE Liner |
| Compliance | DOT Approved |
What’s Included
- Rear brake flexlines (pair)
- Mounting hardware
About Wilwood
Wilwood Engineering has designed and manufactured high performance brake systems for street, off road, and racing applications for decades. Their stainless steel flexlines are built to the same standard as their brake kits, giving daily drivers and racers alike a firmer, more consistent pedal.
Related Parts on Our Site
- Wilwood 221-17396 Front Flexline – Audi A4
- Wilwood 221-17398 Rear Flexline – Audi A4
FAQ
What is the Wilwood 221-17415?
The Wilwood 221-17415 is a braided stainless steel rear brake flexline kit designed to replace the factory rubber brake hose on 1996-2001 and 2004-2009 Audi A4 models.
Why does the fitment skip 2002-2003?
The Audi A4 brake line routing changed between the B5 and B6/B7 chassis generations, so this kit covers the 1996-2001 and 2004-2009 model years but not the 2002-2003 transition years.
Will this flexline fit my A4?
This kit fits 1996-2001 and 2004-2009 Audi A4 model years at the rear position. Check your vehicle’s model year against the fitment table above to confirm.
Is this brake line DOT legal for street use?
Yes, the Wilwood 221-17415 is DOT compliant and legal for street use.
Do I need to bleed the brakes after installing this flexline?
Yes, the brake system must be bled after installation to remove any air introduced during the swap.
Does this kit include the front flexlines as well?
No, this listing is for the rear position only. A separate front flexline kit is available if replacing all four corners.
What material is the outer covering on this brake line?
The line uses a braided stainless steel outer covering over a PTFE inner liner for durability and resistance to abrasion.
Can this flexline be used with aftermarket brake calipers?
Yes, as long as the caliper and hardline fittings match the factory thread and connection type, this flexline is compatible with OEM and most aftermarket setups.
Install Instructions
- Raise and safely support the vehicle, then remove the rear wheels.
- Disconnect the factory rubber brake hoses at the hardline and caliper connections.
- Remove the factory hoses and any retaining hardware.
- Install the new Wilwood stainless steel flexlines, connecting them to the hardlines and calipers.
- Torque all fittings to manufacturer specification and secure with any retaining hardware.
- Bleed the brake system to remove air introduced during installation.
- Check for leaks and verify proper pedal feel before returning the vehicle to service.
