Powerflex Rear Sway/Anti Roll (Stabiliser/Stabilizer) Bar Bush/Bushing Kit 21.5mm Pair - Polyurethane/Urethane ARB Mounts - BMW Z4 M Z4M E85 E86 2006-2009 - PFR5-4609-21.5 OEM 31352229711

Powerflex PFR5-4609-21.5 Rear Stabiliser Bar Bush Kit 21.5 mm - BMW Z4 M E85 E86 2006-2009

Unlock sharper chassis response and rock-solid rear-end control on your BMW Z4 M with this Powerflex 21.5 mm rear stabiliser bar bushing set. By replacing tired factory rubber with performance polyurethane, you gain crisper steering input, flatter cornering, improved traction and far more consistent geometry under load. A simple, high-value suspension upgrade for fast road driving and track days.

We install these on customer Z4 M platforms at MJ Modifications and the results are superb. Expect tighter control, better balance and confidence-inspiring stability without a harsh ride. Supplied as a matched pair with the Powerflex lifetime warranty for long-term peace of mind.

Why this upgrade works

• Holds alignment under cornering and braking for predictable handling
• Reduces roll and rear-end squirm to boost grip and driver confidence
• Fast, precise steering feel and improved turn-in on B-roads and circuit
• Polyurethane resists oil, salt and heat better than rubber for lasting performance
• Direct replacement fitment with minimal increase in cabin noise or vibration
• Helps protect tyre wear by controlling unwanted deflection

Fitment information

• Vehicle - BMW Z4 M E85 Roadster and E86 Coupe 2006 to 2009
• Location - Rear stabiliser bar mounting points
• Bar diameter - 21.5 mm - please measure your rear bar before ordering
• Pack contents - 2 x bushes
• Diagram reference - 4
• Powerflex part number - PFR5-4609-21.5
• OEM reference for cross-check only - 31352229711

Installation and support

Professional fitting recommended. MJ Modifications in Warwickshire offers supply, installation and four-wheel alignment for optimal results. Request a quote at info@mjmodifications.co.uk.

Trusted performance

Customers consistently report flatter cornering, better rear axle composure and a more precise feel once these urethane mounts are installed. It is a proven, cost-effective handling upgrade for the Z4 M that delivers on the road and at the circuit.

Search terms customers use

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