GM Engine Mount PR Clamshell Small

The Prothane GM Engine Mount PR Clamshell Small (Part Number 7-506) is a polyurethane motor mount insert engineered to reduce engine movement and vibration in General Motors vehicles from 1973 through 1993. This small clamshell-style mount replaces worn OEM rubber isolators, restoring chassis rigidity and improving throttle response while maintaining drivability on public roads.

Measuring 6.2 x 3.7 x 6.2 inches and weighing 3.3 lbs, this compact insert fits within the existing engine bay geometry without modification. Polyurethane construction offers superior durability compared to aged rubber, resisting oil exposure, temperature extremes, and UV degradation common in long-term storage or high-mileage applications. The red color serves as a visual identifier during installation and maintenance. The clamshell design allows for straightforward replacement of the worn insert without removing the entire mount assembly, reducing labor time and diagnostic complexity.

This product is suited for classic car restoration, performance upgrade projects, and fleet maintenance on first-generation through fourth-generation small-block and big-block GM platforms. Technicians working on 1973–1993 Chevrolet, Pontiac, Oldsmobile, and Buick models will find this mount particularly useful when diagnosing steering wheel vibration, excessive engine rock during acceleration, or transmission clunk on gear changes—symptoms typically caused by degraded OEM rubber isolators.

Prothane polyurethane components have become an industry standard for restoring chassis compliance in vintage American muscle and truck applications. The small clamshell format fits tighter engine bay spaces where full-size mounts would interfere, making it an economical choice for targeted vibration control without full suspension rework.