Powerflex Polyurethane Rear Subframe Bush/Bushing & Differential Mount Insert Kit – BMW F20 F21 F22 F23 F30 F31 F32 F33 F36 (1/2/3/4 Series F2x F3x) – Rear Cradle/Axle Carrier Poly Bushes – Fast Road/Track Upgrade PFR5-1920/1921/1927

Rear axle stability upgrade for BMW F2x and F3x chassis

Sharpen the back end of your BMW with this Powerflex polyurethane insert kit. It tightens the rear cradle and differential mounts to deliver cleaner traction, crisper turn in and consistent alignment under load. Ideal for fast road and track day use, and equally brilliant on daily drivers that want a more planted, confidence inspiring feel.

Diagram reference: 20, 21 and 27

What you get

• Rear axle carrier front inserts (pair) — Part number: PFR5-1920
• Rear axle carrier rear inserts (pair) — Part number: PFR5-1921
• Rear differential rear mount inserts (pair) — Part number: PFR5-1927

Why choose this upgrade

• Reduces movement in the rear cradle and diff mounts for more precise handling
• Improves traction on corner exit and reduces wheel hop and axle tramp
• Enhances braking stability and steering response from the rear
• Helps maintain geometry under acceleration and over bumps for more even tyre wear
• Polyurethane construction manages NVH effectively while increasing control
• Backed by the Powerflex Lifetime Warranty for long term peace of mind

How it works

These precision moulded polyurethane inserts locate into the voids of the factory rubber mounts. By filling the free space in the original bushes, they reduce unwanted compliance in the subframe and differential mounting points without the need to press out the OE parts. The result is a tighter, more connected rear end and better drivetrain control with minimal added harshness.

Vehicle compatibility

• BMW 1 Series — F2x
• BMW 2 Series — F2x
• BMW 3 Series — F3x
• BMW 4 Series — F3x

Not suitable for M2, M3 or M4 models.

Tried and trusted by us

We have fitted this setup to numerous customer cars and the feedback is consistently positive. Owners report a noticeably more composed rear, better throttle-on stability and a more predictable chassis when pressing on.

Professional fitting

Want it installed by specialists who know F-series BMWs inside out? Book fitting with MJ Modifications in Warwickshire. Request a quote at info@mjmodifications.co.uk.

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