BMW 3 Series / 5 Series / Z4 / Toyota Supra Transmission Mount Bushing

PFF5-4655 is a transmission mount that will fit many different models of BMW throughout the years. This is available in 3 different versions.

• Street: Yellow 70A Durometer

• Performance: Purple 80A Durometer

• Race: Black 95A Durometer

• Heritage: 70A Durometer

These bushings are designed with street and track in mind to replace the tear-prone soft rubber mounts, which is a common cause of knocking, mis-shifting and over-revving.

Made using CNC machined Aluminum Caps with captive securing bolts and a Yellow 70A Durometer polyurethane body, they increase stiffness over OE by 150%, while minimizing NVH transmission.

Aside from our Street Series offering, they are available in our stiffer Purple 80A material for Performance use (260% stiffer) and Black Series 95A material, mainly intended for track use (375% stiffer) for those wanting to further reduce drivetrain movement. The harder the material used, the less deflection they offer and the higher the NVH transmission.

OE / OEM Cross Reference Numbers: OEM Part Number: 2231679331 / 22316771219 OEM Part Number: 23711137817 / 22316796617 OEM Part Number: 22316875904 / 22312284819

How to Choose Powerflex Bushings & Durometer

Powerflex bushings are available in different polyurethane durometers to suit street, performance, track, and restoration applications. The correct bushing depends on how the vehicle is used and the amount of stiffness and chassis control desired.

What Do Powerflex Bushing Colors Mean?

Powerflex uses different colors to identify polyurethane hardness, measured on the Shore A durometer scale:

Red – 65A
Yellow – 70A
Purple – 80A
Black – 95A

A higher durometer generally means a stiffer bushing with less deflection. Powerflex engineers select the appropriate durometer for each specific bushing application to balance performance, durability, and driving characteristics.

Powerflex Road Series – Street & Performance

Powerflex Road Series bushings are designed for street and performance vehicles. They reduce unwanted suspension movement compared with standard rubber bushings, helping maintain suspension geometry and tire contact with the road.

Road Series bushings are a good choice for daily driven vehicles, spirited street driving, and performance builds where improved handling is desired without using Powerflex's stiffest track-focused compound.

Powerflex Black Series – Track & Motorsport

Powerflex Black Series bushings use Powerflex's stiffest polyurethane compound and are designed for track and motorsport applications where maximum chassis and suspension control is the priority.

The Black Series material can be up to 80% more resistant to load than standard rubber and approximately 25% stiffer than Powerflex's purple performance material.

Choose Black Series bushings for dedicated track cars, race cars, and performance builds where minimizing suspension deflection is more important than maintaining street-oriented comfort.

Powerflex Heritage Collection – Classic & Collector Cars

Powerflex Heritage Collection bushings provide the performance and durability benefits of polyurethane while maintaining a more original appearance.

They use the same premium polyurethane technology as the Powerflex Road Series but feature a dark grey finish designed to resemble traditional rubber bushings.

Heritage Collection bushings are ideal for classic, vintage, and collector vehicles where improved suspension performance is desired without changing the factory-style appearance.

Which Powerflex Bushings Should I Choose?

For most street and performance vehicles, Powerflex Road Series bushings provide a balance of improved handling and everyday usability.

For dedicated track or race vehicles, Powerflex Black Series bushings provide maximum stiffness and chassis control.

For classic or collector vehicles where maintaining an OEM-style appearance is important, Powerflex Heritage Collection bushings are the best fit.