2014-2020 BMW i8 Bumper Shock: What to Inspect Behind the Bumper Cover

Bumper Shock vs. Suspension Shock: A Critical Distinction for i8 Owners

When discussing 'shocks' on a BMW i8, it's crucial to understand the difference between two distinct parts, as one has a significant history of problems.

• Bumper Shocks (Energy Absorbers): These are the subject of this guide. They are typically made of foam or collapsible plastic and are part of the bumper assembly. Their only function is to absorb impact during a collision. They have no effect on ride quality.
• Suspension Shocks/Struts: These are hydraulic dampers that are part of the suspension at each wheel. They control the i8's ride quality and handling. The i8 uses electronically controlled shocks (EDC) that adjust stiffness between Comfort and Sport modes. These are known to have failure issues, which are detailed further down.

If your car feels bouncy or makes noise over bumps, you are experiencing a suspension shock issue, not a bumper shock problem.

Symptoms of a Bad Bumper Shock (Energy Absorber)

Unlike most mechanical parts, a bumper energy absorber doesn't wear out over time or produce clear symptoms before it fails. Failure is almost always the result of a physical impact.

• Visible Damage After a Collision: The most obvious sign of failure is visible damage. After any minor front or rear-end collision, the bumper cover should be removed to inspect the energy absorbers. They may be cracked, crushed, or completely broken.
• Loose or Misaligned Bumper Cover: If the energy absorber is broken or its mounting points are damaged, it may not be able to properly support the bumper cover. This can result in a bumper cover that appears loose, sagging, or has uneven gaps with the adjacent body panels.
• Discovered During Other Repairs: Often, a failed bumper absorber is only discovered when the bumper is removed for unrelated service or cosmetic repair.

Known Issues, TSBs, and Recalls for the 2014-2020 BMW i8

Bumper Shocks (Energy Absorbers)

There are no widespread factory defects, Technical Service Bulletins (TSBs), or recalls specifically related to the front or rear bumper energy absorbers on the 2014-2020 BMW i8. Failure is almost exclusively caused by collision damage.

Suspension Shocks (A Common i8 Failure Point)

While not the primary focus of this guide, it is important for any i8 owner to be aware of the well-documented issues with the vehicle's suspension shocks, particularly on earlier models.

• Premature Rear Shock Failure: Numerous owners of 2014-2016 models have reported catastrophic failure of the rear suspension shocks, sometimes with low mileage. The shock can leak all of its fluid or, in some cases, physically snap. This results in a loud clunking noise, extremely poor handling, and a bouncy ride.
• Deteriorating Dust Boots: The root cause of many failures is the premature deterioration of the rubber dust boot (also called a gaiter) that protects the shock's piston shaft. When this boot cracks and falls apart, road debris and water can contaminate the shock's main seal, causing it to fail and leak fluid.
• Updated Part Number: BMW released an updated rear shock absorber to address the failures. The improved part number is 37106884588, which has since been superseded by 37106890693. Owners report that this revised part is more robust.

There are no official recalls for this issue, but some owners have reported that dealers replaced the parts under warranty or as part of a TSB. If you are experiencing suspension problems, it is worth investigating this known issue.

Buying a Used Bumper Shock

A used OEM bumper energy absorber is a great way to save money, as it is a simple component with no electronics. However, careful inspection is essential because its entire purpose is to be destroyed in a crash.

• Check for Any Signs of Compression: The most important check is to ensure the absorber has never been in an impact. Look for any signs that it has been crushed, even slightly. Compare it to photos of a new part. Any deformation means it cannot provide the intended level of protection and should be rejected.
• Inspect for Cracks: Examine the entire part, especially around the mounting points, for any hairline cracks or stress marks. The plastic can become brittle over time, and a small crack can compromise its structural integrity.
• Verify All Mounting Tabs are Intact: Ensure that all tabs, clips, and holes used to attach the absorber to the bumper reinforcement and bumper cover are present and undamaged. Broken tabs will result in a poor fit and a loose bumper cover.
• Source from a Non-Collision Vehicle: The best practice is to purchase a used bumper absorber from a vehicle that was dismantled for reasons other than a front or rear collision. This provides the highest confidence that the part is undamaged.

Cost Comparison for BMW i8 Bumper Energy Absorber

These costs are for a single front energy absorber. Rear absorbers are priced similarly. The primary cost in replacement is the labor to remove and reinstall the bumper cover.

Frequently Asked Questions (FAQ)