Heavy Duty Engine Mounts

Heavy duty engine mounts are the foundation of engine stability and drivetrain longevity in classic muscle cars and street machines. This bolt-on motor mount kit (MPN 90058) is engineered for GM G-Body platforms manufactured between 1978 and 1988—vehicles like the Chevrolet Monte Carlo, Pontiac Grand Prix, and Oldsmobile Cutlass that demand reliable power transfer without excessive vibration. Factory rubber mounts degrade over time, causing motor sag, increased cabin vibration, and transmission slop that compounds wear on the drivetrain. A quality replacement mount restores proper geometry and isolates engine harmonics, making this an essential upgrade for any enthusiast planning serious driving, turbo conversion, or small-block swap.

This heavy duty engine mount kit features steel construction with black powder coat finish, delivering corrosion resistance and durability under underhood conditions. The solid steel design minimizes flex compared to stock rubber mounts, transferring power more directly to the frame while reducing parasitic motion that wastes horsepower and stresses suspension bushings. At 4.15 pounds, the complete kit provides the mass necessary for effective dampening without adding substantial curb weight. Hardware is included, eliminating the need for sourcing fasteners and ensuring proper bolt compatibility with original G-Body mounting points. The compact footprint (4.5 x 4.5 x 12.2 inches) integrates seamlessly into factory engine bay dimensions without requiring additional modifications or custom fabrication.

G-Body owners restoring original performance, installing LS conversions, or upgrading to high-output crate engines will benefit most from this application-specific mounting solution. The kit's bolt-on design allows installation without engine removal on most G-Body configurations, reducing labor time and shop costs. Mechanics and builders appreciate that all fasteners are pre-selected for proper torque specifications and clearance, eliminating guesswork during assembly. Direct fitment is confirmed for 1978–1988 G-Body chassis, ensuring compatibility with Monte Carlo SS, Grand Am, Regal, and Cutlass models. Installation typically requires basic hand tools and takes two to four hours depending on engine bay accessibility and existing mount condition.