Powerflex PFF5-4101 Front Radius Arm to Chassis Polyurethane Bush Kit for BMW 1 Series F20/F21 xDrive - Front Control Arm Rear/Wishbone Bushes (Pair)

BMW 1 Series F20 F21 xDrive Tension Strut Rear Bush Upgrade - PFF5-4101

Sharpen turn-in, boost braking stability and restore precise front-end control with this uprated polyurethane bushing set for the front lower arm rear mounting on xDrive models. Supplied as a matched pair, PFF5-4101 replaces the soft, ageing rubber at the rear of the tension strut, also known as the thrust arm, reaction rod, caster arm or front lower control arm rear mount.

We run these bushes on our own builds and customer cars, and the difference in steering feel, consistency and tyre wear has been superb. If you are refreshing the front suspension on a BMW 1 Series F20 or F21 xDrive, this is a proven, long-term solution for fast road and track day use, as well as a rock-solid OEM+ replacement for daily driving.

Why this polyurethane bushing kit

• Part number: PFF5-4101
• Vehicle: BMW 1 Series F20 F21 xDrive - all-wheel drive variants
• Location: Front lower arm rear mounting to the subframe - often called tension strut rear bush, thrust arm bush, reaction arm bush, caster arm rear bush, front lower arm rear mount
• Contents: 2 x bushes - left and right - diagram reference 1
• Offset sleeve mirrors OE geometry to maintain caster and alignment
• High-grade polyurethane limits unwanted compliance for tighter handling and improved road contact
• Noticeably cleaner steering response, better turn-in and more confidence under braking
• Helps reduce uneven tyre wear and tramlining
• Direct-fit replacement for tired factory rubber
• Powerflex Lifetime Warranty

Ideal for a front-end refresh

Factory rubber compliance bushes soften with age and mileage, leading to vague steering, wandering under braking and accelerated tyre wear. This performance poly solution controls arm movement so your springs, dampers and tyres can work as intended, while preserving everyday comfort levels. It is an essential upgrade when chasing a sharper chassis on an F20 or F21 xDrive.

Technical details

• Engineered offset bore to replicate the original mounting position - preserves caster and geometry
• Direct replacement - no permanent modification required
• OE cross-reference: 31126854729 for verification

Fitting and alignment

Professional installation followed by a full four-wheel alignment is strongly recommended to maximise performance and tyre life. For expert fitting, choose MJ Modifications in Warwickshire. Request a quote at info@mjmodifications.co.uk.

Common searches this kit covers

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