Transmission Mount for 1987 GMC S15 Base

GMC S15 Transmission mounts are the platform-specific polyurethane bushing kits, mount bushing replacement kits and complete mount assemblies used to replace worn or deteriorated rubber components at the transmission mount, gearbox crossmember, torque arm and related drivetrain support positions. The transmission mount is the primary chassis support for the rear of the transmission, carrying a share of the transmission's weight and resisting the torque reaction loads that the drivetrain generates under acceleration and deceleration. On RWD platforms, the rear transmission mount also works alongside the torque arm and crossmember mount to control drivetrain movement within the chassis. On FWD platforms, multiple transmission mount positions work together to locate the transversely mounted engine and transmission assembly and resist the torque reaction that every throttle input generates.

As transmission mount bushings deteriorate through heat cycling, oil contamination and sustained torque loading, compliance at the mount increases, allowing the transmission to shift within the chassis under load. The result is drivetrain thump under gear changes and throttle application, increased NVH transmitted through the transmission tunnel and floor, and progressive wear on driveshafts, exhaust and other components stressed by excess transmission movement. The range covers gearbox crossmember pad bushings, complete transmission mounts, transmission mount bushing replacement kits, manual and automatic transmission mount bushing sets, gearbox positive shift kit bushings, torque arm mounts, high performance transmission mount assemblies, transmission mount bushings in platform-specific configurations, a lower transmission torque mount set and shifter stabilizer bushings. Warranties range from limited lifetime to 3 years. Installation guides are available across most products.

Why Upgrade GMC S15 Suspension?

Transmission mount wear produces a recognizable set of drivetrain symptoms that worsen progressively with mileage: a thump or jolt as the drivetrain loads and unloads under gear changes, vibration transmitted into the cabin through the transmission tunnel, and a looseness in the drivetrain's feel under hard acceleration that reflects the increasing freedom with which the transmission is moving within its mount. On high-output, performance and modified platforms, transmission mount wear is accelerated by the elevated torque loads these applications generate, and the symptoms appear earlier and more noticeably than on standard vehicles.

Renewing GMC S15 transmission mount bushings and complete mount assemblies with correctly specified polyurethane alternatives restores correct transmission location and significantly reduces transmitted NVH. Polyurethane's improved deformation resistance under repeated torque loading delivers extended service life under the same conditions that caused the original rubber failure. On applicable manual transmission platforms, the gearbox crossmember pad bushing and positive shift kit bushing work in combination to reduce the compliance that produces vague shift quality and gearbox movement, delivering improved transmission feel alongside the reduced NVH that correct mount condition provides.

GMC S15 Transmission Mount Range

The GMC S15 transmission mount range includes:

• GMC S15 Gearbox Crossmember Pad Bushings, Manual Transmission: Polyurethane crossmember pad bushing kits for the gearbox crossmember mount position on applicable manual transmission platforms, reducing gearbox movement at the crossmember and contributing to improved shift quality alongside reduced drivetrain NVH.
• GMC S15 Complete Transmission Mount Assemblies: Full replacement transmission mount assemblies for applicable RWD platforms requiring complete mount assembly renewal at the rear transmission mount position.
• GMC S15 Transmission Mount Bushing Replacement Kits: Polyurethane bushing replacement kits for the transmission mount position on applicable passenger and performance platforms, installing into the existing mount shell without requiring full mount assembly replacement.
• GMC S15 Manual Transmission Mount Bushing Sets: Polyurethane bushing sets for the manual transmission mount positions on applicable FWD performance and passenger platforms.
• GMC S15 Automatic Transmission Mount Bushing Sets: Polyurethane bushing sets for the automatic transmission mount positions on applicable passenger platforms.
• GMC S15 Gearbox Positive Shift Kit Bushings, Manual Transmission: Polyurethane positive shift kit bushing kits for the gearbox mount and crossmember position on applicable manual transmission FWD platforms, reducing gearbox compliance to deliver more positive, direct shift engagement.
• GMC S15 Torque Arm Mounts: Polyurethane torque arm mount kits for the torque arm mount position on applicable RWD performance platforms, controlling longitudinal drivetrain torque reaction at the torque arm chassis mount. Available in the applicable orientation for the specific torque arm mount configuration.
• GMC S15 High Performance Transmission Mount Assemblies: Complete high performance transmission mount assemblies for applicable RWD performance and Applicable performance platforms, built to a higher specification than standard factory replacement mounts for improved mount rigidity and reduced drivetrain movement under performance driving loads.
• GMC S15 Transmission Mount Bushings, Platform-Specific: Platform-specific transmission mount bushing kits for applicable passenger, performance and 4WD platforms in a range of configurations for front and rear mount positions.
• GMC S15 Lower Transmission Torque Mount Sets: Polyurethane lower transmission torque mount bushing sets for the lower torque mount position on applicable FWD performance and passenger platforms, controlling the lower torque reaction at the transmission mount interface.
• GMC S15 Shifter Stabilizer Bushings: Polyurethane shifter stabilizer bushing kits for the shifter stabilizer position on applicable FWD manual transmission platforms, cross-listed at the transmission mount position for platforms where the stabilizer bushing is part of the gearbox mount assembly service.
• GMC S15 Gearbox Crossmember Pad Bushings, Additional Platforms: Gearbox crossmember pad bushing kits for additional applicable FWD platforms requiring crossmember pad bushing renewal at the applicable gearbox mount position.

Why Purchase GMC S15 Transmission Mounts?

Transmission mount wear is one of the most impactful drivetrain service items in terms of the immediate improvement that renewal delivers. The thump, NVH and drivetrain looseness that worn mounts produce are eliminated from the first drive after correctly renewed mounts are installed, and the difference between worn and renewed transmission mounts is immediately apparent under normal driving conditions. Complete mount assembly replacements address the full mount condition at once, while bushing replacement kits that install into the existing mount shell provide a more accessible renewal path on applicable platforms with reduced installation complexity.

For manual GMC S15 transmission platforms where the gearbox crossmember and positive shift kit bushings contribute to shift quality as well as drivetrain location, renewing all mount-related bushings together as part of a single drivetrain service ensures the full improvement in shift quality and NVH reduction is achieved simultaneously rather than progressively.

Installation and Support

GMC S15 Transmission mount kits and assemblies install at the front and rear transmission mount, crossmember, torque arm and lower torque mount positions on applicable platforms. Installation times range from under an hour for simple bushing kits to two hours for full mount bushing set and crossmember pad bushing installations. Bushing replacement kits install into the existing mount shell without requiring full assembly removal on applicable platforms. Installation guides are available across most products. For additional technical assistance, a dedicated support team is available to confirm correct product selection, transmission configuration and fitment for the specific platform and mount design.

Repair and Upgrade

GMC S15 Transmission mount components are manufactured from high-strength polyurethane and quality materials engineered to withstand the sustained transmission weight, torque reaction loads, heat cycling and oil contamination that transmission mount positions are subject to across all driving conditions. Polyurethane resists deformation and heat degradation more effectively than factory rubber alternatives under the elevated and repeated torque loads of performance and high-output applications, delivering longer service life and more consistent mount compliance throughout the renewed installation's service life. High performance transmission mount assemblies are built to a higher specification than standard factory equivalents for improved mount rigidity under performance driving loads. Warranties range from limited lifetime to 3 years depending on the product.

Who GMC S15 Transmission Mounts Are For

GMC S15 Transmission mounts are a practical solution for:

• Professional shops completing drivetrain overhauls, transmission services and performance builds on applicable passenger and performance platforms requiring transmission mount bushing renewal or complete mount assembly replacement to eliminate drivetrain thump, reduce transmitted NVH and correctly locate the transmission within the chassis.
• Performance and enthusiast vehicle owners renewing transmission mount assemblies or bushing kits with polyurethane alternatives on applicable RWD and performance platforms where factory rubber mount life is limited by elevated torque loads and performance driving conditions.
• Manual transmission owners on applicable FWD platforms requiring combined crossmember pad bushing, positive shift kit bushing and transmission mount bushing renewal to restore the full improvement in shift quality and drivetrain NVH reduction that correct transmission mount compliance provides.

The right transmission mount kit restores correct transmission location and mount compliance at every renewed position, eliminates drivetrain thump and transmitted NVH, and delivers a correctly supported and correctly located transmission from the first drive after installation.

Shop GMC S15 Transmission Mounts

Explore the full GMC S15 transmission mount range and find the right kit for your vehicle. With gearbox crossmember pad bushing kits, complete transmission mount assemblies, transmission mount bushing replacement kits, manual and automatic transmission mount bushing sets, positive shift kit bushings, torque arm mounts, high performance transmission mount assemblies, platform-specific transmission mount bushings, lower transmission torque mount sets and shifter stabilizer bushings across applicable passenger, performance, 4WD and RWD platforms, you can restore correct transmission mount compliance and complete every drivetrain service with confidence.