Jaguar XJ8 Suspension Fault & Spring Conversion Information

Jaguar X350 2004-2006 XJ8 Air Suspension Problems

As the owner of one of these beautiful cars, it's likely you've encountered a few troublesome issues with the vehicle's air suspension system (count yourself among the few if you have not!) Take a glance at the lists below, and if any of it rings true with your experiences please continue reading - we believe you'll be glad you did.

Symptoms of Air Suspension Problems

  • Air Suspension Warning Light
  • Message Center: Vehicle too Low
  • Possible Codes: C2302, C2303, B1671
  • Inconsistent Suspension Performance and Operation
    • Poor Ride Quality
    • Intermittent and Unexplained Changes in Vehicle Ride Height

Reasons for Air Suspension Problems

  • Cold and/or Freezing Weather Temperatures
  • Air Compressor Failure
  • Low voltages and Other Electrical Issues
  • Leaks in Air Shocks and Air Delivery Lines
  • Loose Fittings

The Once and for All Solution to the XJ8 Air Suspension Problem

Blackdog Manufacturing, the exclusive in-house manufacturing division of British Parts International and Motorcars, Ltd. announces availability of the XJ8 Air Suspension Conversion Kit. This coil spring/shock absorber kit is an economical and permanent solution to the troublesome 2004-2006 XJ8 factory air suspension system. The system utilizes the proven and time tested coil spring/shock assembly design and features Bilstein shock absorbers. The suspension kit includes all necessary components to eliminate any warning light or ECM code issues. The spring/shock assemblies use the vehicle's existing suspension mount points, so installation requires no cutting or welding.

Installing the Air Suspension Conversion kit on your vehicle will provide for comfortable, trouble-free driving for years to come! Check out these videos:


If you have questions, please contact our sales department by phone or our contact form: (800) 338-5238. Download a PDF copy of the XJ8 Air Suspension Conversion product data sheet here.

XJ8 Spring Conversion Product Comparison

If you are considering purchasing a kit from another supplier, please read the following product comparison.

We've sold and installed hundreds of "Black Dog" spring conversion kits since its release on April 14, 2011. Now, a few short months later, a competitor has released their version of a spring conversion kit for the 2004-06 Jaguar X350 XJ8. They claim their kit is original, and claim to have exclusive availability of any such kit on the market!

Yes, our spring conversion kit costs a little more, but we firmly believe this is not a decision to be made on price alone. Before making a decision, we encourage you to carefully consider the information below, then compare the kits "apples to apples". We are confident that ours is a superior kit in every respect and that it will be the obvious choice! If price remains the single determining factor, remember the old adage: “You get what you pay for.”

Quality Design & Engineering

  • Engineered and Designed by a Jaguar Specialist
  • Coil Springs Designed Specifically for an "Original Ride" Feel
  • Manufactured by Black Dog Remanufacturing exclusively for the Motorcars conversion kit

Handling & Ride Characteristics

  • Preferred Rake and Ride Height
  • Provides the Smooth Ride Jaguar Owners Expect
  • Offers Firm Handling in Aggressive Situations

Codes & Warning Light Issues

  • Maintains Full Functionality of the Computer System
  • Wiring Modifications Were Engineered for Seamless Integration with the Vehicle's On-Board Diagnostic System and Suspension Options
  • Will Not Disable Self-Leveling Head lamps

Parts Quality

  • Utilizes Factory Jaguar Components
  • Original Equipment Application Specific Bilstein Shocks – Jaguar's Shock of Choice
  • OEM Style Top Plates use Rubber and Molded Foam Plates Specifically Designed to Preserve the Original Smooth and Quiet Ride Jaguar owners expect


  • Easy to Follow Instructions
  • Installation Videos Available Online
  • No Core Charge and No "Double Speak"

The Black Dog / Motorcars kit is a superior product in every respect with quality beyond reproach. You actually do get what you pay for in this world and the difference between the two kits is expressed in the offering prices…ours costs more, for a reason.

Components Yes! Designed & Assembled with Jaguar Factory Components Who Knows? Undisclosed
Top Plates Molded OEM style flexible rubber and molded foam Top Plates ?? Rigid Top Plates
Shocks Rugged Bilstein Shocks Specified by Jaguar for Jaguars Who Knows? Shock of Unknown Specification
Wiring Integrated! Wiring Mods Integrate Seamlessly with Diag & Suspension Systems Nope No Integration - Simply “Unplugs All of the Wires”
Functionality Full Functionality! Computer Maintains Full Functionality Nope Some Functionality May be Compromised

Click here for your kit!

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