TGK Motorsport Rear Spherical Strut Perch

The factory rear strut mount uses a rubber isolator that allows the strut to move under load. While this helps reduce noise and vibration, it also introduces compliance that directly affects rear suspension behavior—especially during cornering, braking, and rapid load transitions.

The TGK Motorsport Billet Rear Spherical Strut Perch replaces the rubber mount with a precision spherical bearing assembly, removing unwanted deflection while allowing the strut to articulate smoothly through its full range of motion.

Why the Factory Rear Mount Is a Limitation

Rubber rear strut mounts compress and deform when load is applied. Under acceleration, braking, or lateral force, the strut can shift relative to the chassis. That movement changes suspension geometry moment-to-moment, making the rear of the car less predictable and harder to control at the limit.

This compliance becomes more noticeable on vehicles with stiffer springs, coilovers, wider tires, or increased grip—where the suspension is asked to do more work and rubber isolation becomes a liability rather than a benefit.

TGK Motorsport Design Approach

This perch was designed to remove compliance without introducing binding or harshness from misalignment. The solution is a rigid, billet housing paired with a PTFE-lined spherical bearing that supports load while allowing free angular movement of the strut shaft.

The result is a rear mount that behaves consistently under load while maintaining proper suspension articulation.

Key Design Features

Billet 6061-T6 Aluminum Construction

CNC-machined from solid 6061-T6 aluminum for strength, dimensional stability, and long-term durability. The rigid housing prevents deformation under load and provides precise bearing alignment.

PTFE-Lined Spherical Bearing

The self-lubricating spherical bearing allows smooth, unrestricted strut movement without binding or maintenance. Unlike rubber, it does not compress or deflect under load, keeping the suspension geometry stable.

Function-First Rear Mount Design

The design eliminates the compliance of the factory rubber mount while preserving the angular motion required for proper strut operation. Load is carried cleanly through the bearing instead of being absorbed by deformable material.

What Changes with a Spherical Rear Mount

Eliminates Rear Suspension Deflection

With the rubber isolator removed, the rear strut no longer shifts under load. Suspension response becomes immediate and repeatable, particularly during transitions and mid-corner loading.

Improves Stability and Chassis Balance

By keeping the rear suspension geometry fixed, the car reacts more predictably to throttle, braking, and steering input. This improves rear-end stability and helps maintain balance through corners.

Maintains Alignment Under Load

Rubber mounts allow subtle alignment changes as they compress. A spherical bearing holds the strut in a fixed position relative to the chassis, keeping camber and toe consistent when the suspension is loaded.

Increased Durability in High-Load Use

Rubber mounts degrade from heat, repeated load cycles, and environmental exposure. A PTFE-lined spherical bearing is designed for sustained mechanical load and aggressive use without deterioration.

Intended Use

Performance-oriented street vehicles

Track-driven cars

Rear strut or coilover applications

Builds where rear suspension precision and consistency matter