SPL Parts BMW F2X/F3X Front Caster Rod/Tension Strut (Thrust Arm) Bushings, Non-Adjustable - FK 1in Teflon-Lined Spherical Bearings - Fits F22 F23 F30 F31 F32 F33 F36 RWD (No xDrive) - SPL CRBN F3X

SPL Parts front radius arm monoball kit for BMW F2X and F3X RWD

Give your BMW 2 Series, 3 Series or 4 Series a sharper front end and confident braking with SPL Parts’ motorsport-grade replacement for the factory rubber in the forward lower arm. This upgrade swaps the stock compliance for FK 1 inch PTFE lined spherical bearings to deliver laser-precise steering, improved stability on the brakes and repeatable performance on fast road and track.

Why enthusiasts choose this upgrade

• Transforms turn-in and front-end bite for more immediate response
• Reduces brake shimmy and wandering for a calmer steering wheel at speed
• Keeps alignment true under load so grip and feedback stay consistent
• Retains factory geometry in a non adjustable package focused on feel and control

Built to last

• FK 1 inch Teflon lined spherical bearings for ultra smooth articulation and low friction
• CNC machined 6061 T6 aluminium housings with knurled exterior for secure press fit
• Motorsport spec construction designed for demanding use
• Sold as a matched pair
• Made in the USA

Also known as

Radius rod bearings, traction arm monoballs, reaction rod bearings, thrust arm monoball conversion, front wishbone rear bush, forward lower control arm rear mount, lollipop bush upgrade.

Fitment

• BMW F2X 2 Series: F22 and F23
• BMW F3X 3 Series and 4 Series: F30, F31, F32, F33, F36
• Rear wheel drive vehicles only. Not suitable for xDrive or AWD.

Part number: SPL CRBN F3X

Real world results

We have installed this setup on customer cars and our own builds. Feedback is consistently strong: noticeably crisper steering, a planted nose on turn-in and far greater confidence under hard braking. If you are upgrading the forward arm on an F30 or F32 platform car for fast road or track days, this is the spherical conversion we recommend.

Installation and alignment

Professional installation is advised. A press is required to remove the OE rubber and fit the new housings. A four wheel alignment should be carried out after installation to maximise tyre contact and performance. For fitting, contact MJ Modifications in Warwickshire for a quote: info@mjmodifications.co.uk.

What is included

• 1 pair of SPL Parts non adjustable front radius arm monoballs

Search terms

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