Powerflex Black – Upper Gearbox Mount Insert for Toyota GR Yaris

The Powerflex Black Series upper gearbox mount bush insert (PFF76-923BLK) is designed to stiffen the original OEM transmission mount on the Toyota GR Yaris in high-performance applications such as circuit driving, rallying and track days.

Made from Powerflex's special ultra-stiff 95 Shore A Black Series polyurethane compound, this insert fills the voids in the factory rubber bush, firmly stabilising the gearbox housing and upper engine mount (OEM part number: 12372-18010). By reducing transmission twist and movement under hard acceleration and during fast gear changes, it provides a significantly more direct pedal feel, limits driven-wheel wheel hop and transfers power to the road more effectively.

Installation is straightforward and cost-effective because the insert fits inside the factory OEM mount, without requiring replacement of the complete arm. For maximum performance, Powerflex recommends installing it together with the other powertrain inserts designed for the GR Yaris (PFF76-920BLK and PFF76-925BLK).

Features

• Type: Upper gearbox mount bush insert
• Product type: Polyurethane bushes and mounts
• Series: Powerflex Black Series (specifically for track, rally and motorsport use)
• Material: High-performance 95 Shore A polyurethane (black)
• Reference OEM part number: 12372-18010
• Manufacturer part number: PFF76-923BLK
• Quantity per vehicle: 1
• Transmission stability: Reduces gearbox deflection and movement under load and under braking
• Driving response: More precise gear engagement and shifts, sharper pedal response and reduced wheel hop
• Recommended combination: Most effective when installed with Powerflex inserts PFF76-920BLK and PFF76-925BLK
• Direct-fit installation: Simple plug & play installation inside the factory mount

Note

As this is the ultra-stiff Black Series (95A) version intended for motorsport use, installation may increase vibration and noise (NVH) inside the cabin, especially at idle.