Powerflex Black Series Caster Adjustable Front Control Arm/Tension Strut Bushes for BMW 3 Series G20 G21 (2018+) - Radius/Thrust Arm Polyurethane Bushings, Caster Correction Track/Fast Road - xDrive & RWD - PFF5-2501GBLK

Dial in front-end precision on your BMW 3 Series G20 G21 with caster-adjustable polyurethane bushes for the front tension strut. This Powerflex upgrade gives you on-car alignment tuning for sharper steering, better feedback and more stable tracking on fast road and circuit use.

Part number: PFF5-2501GBLK

Why enthusiasts choose this caster correction kit

• On-vehicle caster tuning up to ±0.75° lets you fine-tune geometry for your setup, tyres and driving style.
• Sharper initial response and more direct feel from the wheel thanks to high-performance polyurethane that resists flex better than tired rubber bushes.
• Improved straight-line stability and reduced tramlining, helping to counter pull from road camber or uneven surfaces.
• Consistent alignment under load during hard braking and cornering, ideal for track days and spirited driving.
• Durable, motorsport-focused compound designed to handle heat, load and repeated abuse far better than OE rubber.

What it replaces

• Direct replacement for BMW OE references: 31106894667 and 31106894668

Fitment

• BMW 3 Series G20 and G21, 2018 onwards, saloon and touring
• Front axle tension strut, also known as thrust arm or caster arm
• Diagram reference: 1

In the box

• 2 x front control arm polyurethane bushes

We run these on our own builds and customer cars, and the feedback is consistently positive. Expect crisper turn-in, cleaner mid-corner stability and a more confidence-inspiring steering feel. A must-have suspension upgrade if you are chasing precise wheel alignment and long-lasting performance from your front control arm bushings.

Popular search terms to help you find the right upgrade: BMW G20 suspension bushes, G21 front control arm bushings, caster correction kit, front tension strut bush, thrust arm bush upgrade, polyurethane control arm mounts, alignment adjusters, fast road suspension, track day handling kit, xDrive saloon estate wagon, PU bushes UK.

Professional fitting

For installation, we recommend booking with MJ Modifications in Warwickshire. Email info@mjmodifications.co.uk for a fitting quote.