Pontiac Rattling Noise with Sound Deadening

Pontiac Firebird Rattling Noise & How to Fix It With Sound Deadening

Owners of Pontiac Firebird may notice a rattling noise in the back, especially when driving over bumps or rough roads. This post explains why that happens, outlines diagnostic steps, and shows how using sound-deadening materials, particularly B-Quiet products, can restore a quiet, comfortable ride.

Diagnostics: How to Pinpoint the Rattle

Before applying sound-deadening material (which helps, but isn’t a magic fix for structural issues), go through a systematic check:

1. Drive test

  • Identify when the noise is worst: low speed, high speed, over bumps, during turns
  • Try to replicate the noise in a quiet area, isolate front vs. rear, left vs. right.

2. Inspect suspension components

  • Check ball joints, bushings, sway bar end links, struts, mounts for play or wear
  • Use a pry bar to see movement, or check lift-on-lift-off

3. Interior panels & trim

  • Remove interior panels (rear parcel shelf, kick panels, trunk liner) and shake them individually
  • Look for loosened clips, grommets, or missing foam padding

4. Tap test on panels

  • Gently tap suspect panels and listen for “hollow” or buzzing spots
  • Use a rubber mallet or your knuckle

5. Use cardboard or felt temporarily

  • Hold felt, rubber, or cardboard over suspected spots while driving to “mute” the noise. If it disappears, you've located the source.

Once you confirm the source isn’t a loose fastener or worn mechanical part, sound deadening becomes a highly effective supplementary solution.

How Sound Deadening Works & Why B-Quiet Helps

Sound-deadening (or damping) materials reduce vibration and absorb acoustic energy. They work by:

  • Adding mass to panels so they don’t flex and resonate
  • Sealing gaps and isolating metal-to-metal contact

B-Quiet Ultimate Automotive Sound Deadener is a peel-and-stick butyl/aluminum composite that’s engineered to work in the cabin, beneath carpet, behind panels, and on doors.

We also offer B-Quiet H-Liner, which adds thermal insulation (helpful under the hood or on floor pans) and further acoustic dampening.

Pontiac Firebird Sound Deadening

Step-by-Step: Installing Sound Deadening in a Pontiac

1. Remove seats & carpet / interior panels

  • Unbolt the seats, remove the carpet and padding
  • Remove door panels, kick panels, rear trim, trunk liner

2. Clean and prep the surfaces

  • Use isopropyl alcohol or degreaser to clean bare metal
  • Ensure surfaces are dry & free of rust or peeling paint

3. Cut and test-fit your sheets

  • Use templates or cardboard to cut your pieces
  • Leave ¼ inch margins to tuck under edges and avoid bunching

4. Press firmly

  • Use a roller to eliminate air bubbles

5. Layer strategically

  • On the floor: full coverage under carpet with particular attention near transmission tunnel and footwells
  • Doors: apply to the door skin and interior door cavities
  • Trunk / rear panels: line inner skins and floor pans
  • Underhood (optional): use B-Quiet HLiner to the floor, transmission tunnel, and back wall of your Pontiac for Heat insulation. 

6. Reassemble

  • Replace carpet, trim, and panels
  • Make sure clips and fasteners are tight
  • Gently test doors, hatch, and panels for interference

For a Pontiac, a full application (floor, doors, trunk, some under-hood zones) often takes 2 to 4 hours (depending on skill, tools, and disassembly ease).

Conclusion

A rattling Pontiac doesn’t have to be part of the classic-car experience. With a little inspection, planning, and high-performance sound-deadening materials, you can bring back that solid, quiet muscle-car ride.

Use the B-Quiet Calculator to find out how much material your Pontiac needs, then shop our Car Sound-Deadening Package to skip buying the materials separately and get started today.