GM Clamshell Motor Mount 3 Hole

The Energy Suspension GM Clamshell Motor Mount 3 Hole is a Hyper-Flex polyurethane motor mount designed to replace the factory rubber insert on three-bolt General Motors clamshell-style engine mounts. This mount combines a steel backing plate with red polyurethane elastomer, cadmium-plated for corrosion resistance, to provide superior vibration isolation while reducing engine movement compared to stock rubber components. The 3-hole configuration ensures precise fitment on GM engines equipped with the standard clamshell mount system.

Hyper-Flex polyurethane technology delivers significantly greater durometer hardness and load-bearing capacity than original equipment rubber mounts, translating to less engine rocking during acceleration, deceleration, and gear transitions. The steel reinforcement plate ensures structural integrity under sustained load, while the cadmium plating protects against salt spray, moisture, and prolonged exposure in harsh environments. The compact profile measures 5.8 x 2.7 x 6.75 inches and weighs 1.71 lbs, fitting directly into original mount locations without modification to engine bay hardware.

This mount is engineered for GM vehicles—including truck, SUV, and performance applications—where factory mounts have deteriorated, separated from the steel core, or where reduced engine movement improves driveline alignment and transmission shift quality. It serves as a direct replacement for OEM mounts that have developed cracking, leaking, or excessive play. The upgrade appeals to operators maintaining fleet vehicles, off-road builds, and high-mileage rigs where engine control is critical for reliability and longevity.

Energy Suspension's polyurethane motor mount inserts are widely used in automotive restoration, fleet maintenance, and performance builds as a cost-effective alternative to full OEM mount replacement. The three-hole clamshell design is a common configuration across multiple GM engine generations, making this a versatile upgrade for chassis built between the 1970s and early 2000s. Installation requires no special tools—the insert simply replaces the deteriorated rubber piece within the existing steel clamp assembly.