• Identified Issues
    • Road noise from the wheels
    • Engine Noise
    • High level of vibration and both internal and external noise
    • Doors rattles
  • Work Performed
    • Comprehensive soundproofing
    • External treatment of wheel arches
    • Soundproofing of the front panel
  • Materials Used
    • StP Diamond
    • StP Bromo
    • StP Biplast
    • StP Sonora
    • StP Bitoplast
Photo Report of Completed Work
In this article, we take a detailed look at the factory soundproofing of the Toyota Land Cruiser 76, and share a photo report of the full-body soundproofing process using professional STP materials.
After dismantling the interior, we carefully inspected the stock insulation. The results were expected — no soundproofing at all on the roof and doors, and only small vibration-damping patches on the floor and cargo area, covering roughly 20% of the surface.
Our goal was to transform the LC76 into a quieter, more comfortable vehicle while preserving its rugged character. Using STP Gold, Aero, and Accent series materials, we achieved a dramatic improvement in cabin comfort, reducing road, engine, and body resonance noise.
Roof Sound Proofing
The roof of the Land Cruiser 76 is one of the largest and thinnest body panels, which makes it a major source of wind and rain noise entering the cabin at speed.
To address this, we applied a lightweight yet highly effective 2 mm STP Diamond vibration damping material, designed to significantly reduce metal resonance and roof panel vibrations.
Roof Sound Proofing
As the second layer, we installed STP Accent 10 , a high-quality porous sound absorber that effectively eliminates medium and high-frequency noises, such as wind, rain, and roof panel flutter.

Together, these layers create a solid, quiet, and thermally stable ceiling — making long drives in the LC76 much more comfortable without adding unnecessary weight.

Floor Sound Proofing
The floor was treated with STP Gold 2.3 mm, a high-efficiency vibration damping material designed to handle large, flat metal surfaces exposed to constant mechanical and road impact.
Benefits of Floor SoundproofingReduces aerodynamic and road noise, creating a calmer cabin environment
Minimizes vibration load on the vehicle’s body, extending panel life and improving comfort
Dampens impact noise from gravel, sand, and uneven surfaces hitting the underbody
Improves thermal insulation, keeping the cabin cooler in summer and warmer in winter
This combination provides a noticeable upgrade in both acoustic comfort and driving feel, especially important for long-distance or off-road use of the Land Cruiser 76.
The doors of the Land Cruiser 76 were treated with a two-layer system — STP Diamond as the base vibration damping layer and STP Sonora as the acoustic absorber.
This combination eliminates metal resonance, door panel rattles, and external noise from passing traffic or tyres.

As a result, the doors now close with a solid, premium feel, and the cabin becomes noticeably quieter even at higher speeds.

As a result, the doors now close with a solid, premium feel, and the cabin becomes noticeably quieter even at higher speeds.

Soundproofing plastic panels is just as important as treating metal surfaces. Over time, interior plastics lose rigidity, start to vibrate, and create squeaks or rattles when the car is in motion. By applying anti-squeak materials like STP Bitoplast or Biplast, we isolate these parts from each other, eliminating friction and resonance. This not only removes unwanted cabin noises but also gives the interior a solid, factory-fresh feel.

Contact us
Working hours: 10:00 – 18:00
9/380 Pittwater Rd North Manly

0415 623 634
info@carsounddeadening.com.au