2018-2020 Buick Regal Hood: Fixing Flutter, Alignment, and Active Safety System Issues

Known Issues and Technical Service Bulletins

Hood Flutter or Vibration at Highway Speeds

Some owners may notice the hood panel fluttering, shaking, or vibrating at highway speeds. This is not only distracting but can indicate an underlying issue. There are two primary causes for this:

• Improper Latch or Bumper Adjustment: The most common cause is a misaligned hood latch or improperly adjusted rubber bump stops at the front corners of the engine bay. If the hood isn't held down securely, air pressure at speed can cause it to lift and vibrate. Adjusting the latch down or raising the bump stops can often resolve this.
• Panel Separation: In some cases, the adhesive bonding the inner hood frame to the outer hood skin can fail. This allows the thin outer panel to move independently and flutter in the wind. A General Motors Technical Service Bulletin (TSB 17-NA-065) for other models describes this exact condition and a repair that involves injecting a special panel vibration control material between the layers. While this TSB is not specifically for the Regal, the issue is known to occur on modern vehicles with large, lightweight hoods.

Critical Safety System: Active Hood for Pedestrian Protection

All 2018-2020 Buick Regal Sportback and TourX models are equipped with an active pedestrian protection system. This system uses sensors to detect an imminent impact with a pedestrian at speeds between 16-30 mph. If triggered, it fires small pyrotechnic actuators (similar to those in an airbag) located at the hood hinges. These actuators instantly raise the rear edge of the hood by approximately 4 inches, creating a larger, more deformable crash zone to cushion the impact.

Symptoms of a Failing or Damaged Hood

Since a hood is a body panel, "failure" is typically related to physical damage or issues with its hardware.

• Visible Damage: Dents from hail or impacts, deep scratches that break the paint, and peeling clear coat are the most obvious signs.
• Poor Alignment and Uneven Gaps: If the gaps between the hood and the fenders are uneven or excessively wide, it usually indicates past collision damage or improper installation.
• Difficulty Opening or Closing: A hood that is hard to close or requires slamming may have a misaligned latch or striker. A hood that is difficult to open could have a stretched or broken release cable.
• Hood Pops Open While Driving: This is a critical safety failure, usually caused by a faulty primary or secondary hood latch (GM Part #39086595). If this occurs, the vehicle should not be driven until repaired.
• Hood Won't Stay Open: If you have to prop the hood open, the gas-charged lift supports (struts) have failed and need to be replaced. This is a common wear item.

Buying a Used Hood: What to Check

A used OEM hood is often a better choice than a new aftermarket part because it guarantees proper fitment and material quality. The OEM hood for the Regal is aluminum, which is lighter than the steel used in some aftermarket versions. Here’s what to inspect before buying:

• Overall Condition: Look for major dents, dings, and deep scratches. Minor surface scratches can be fixed during repainting, but deep gouges are more difficult to repair.
• Check for Hidden Repairs: Look at the underside of the hood for any signs of repair, like non-factory welds or mismatched paint. Since the hood is aluminum, a magnet won't work to find body filler (Bondo). Instead, look down the surface of the hood in reflected light for any waviness, ripples, or dull spots that indicate filler has been used.
• Inspect the Edges and Seams: Check the folded seams on the underside for any signs of rust, corrosion, or separation. This is a common area for moisture to get trapped.
• Hinge and Latch Points: Examine the mounting points for the hinges and latch. Look for any cracks, stress marks, or elongated bolt holes that could indicate a past impact.
• Active Safety System: Check the hinge areas for the pyrotechnic actuators. Ensure they are present and do not show any signs of deployment (e.g., ruptured casing, burn marks). If you are buying a hood that includes the hinges, this is especially important.
• Confirm Interchangeability: The hood is the same for both the Regal Sportback and the Regal TourX models from 2018-2020.

Cost Comparison for a 2018-2020 Buick Regal Hood

Prices can vary based on condition, location, and supplier. The costs below are estimates and do not include painting, which is almost always required.

Replacement Overview

• Difficulty: 3 out of 5
• Estimated Time: 1.5 hours (not including painting)
• DIY Feasible: Yes, but it is a two-person job.

Replacing the hood is straightforward but requires a helper to prevent scratching the fenders or windshield. The basic steps involve scribing the current hinge locations, disconnecting the washer fluid hose, unbolting the old hood, lifting it off, and carefully installing the new one. The most time-consuming part is aligning the new hood to achieve even panel gaps all around. This is done by slightly loosening the hinge bolts and adjusting the hood's position before tightening them fully. The rubber bump stops and latch height may also need adjustment to prevent flutter.

Frequently Asked Questions (FAQ)