SPL Parts BMW E8X E9X F8X Adjustable Front Caster Rod/Control Arm Monoball Bushings (Tension Strut/Thrust Arm Spherical Bearings) - E82 E88 E90 E91 E92 E93 F80 M3 F82 F83 M4 F87 M2 - Pair - SPL CRB E9X

SPL Parts Front Radius Arm Spherical Bearing Kit for BMW 1 Series and 3 Series - Part Number: SPL CRB E9X

Transform the front-end precision of your BMW with this SPL Parts front radius rod bearing upgrade. This press-in spherical conversion replaces the soft hydraulic bush in the front locating arm, giving instant steering response, rock-solid braking stability and geometry that stays consistent under load on fast road and track. If you are searching for a front wishbone rear bush upgrade, radius arm bearings, caster correction kit or a thrust arm spherical solution for BMW E8X, E9X and F8X chassis, this is the motorsport-proven answer.

What you will feel

• Sharper turn-in and direct on-centre feel with reduced compliance
• Repeatable alignment during hard braking and cornering, improving confidence
• Adjustable caster via offset spacers to dial in stability and tyre contact
• Cleaner feedback through the wheel for track days, time attack and spirited road driving

Why this kit stands out

• Massive 1 inch FK spherical bearings with self lubricating PTFE liners for durability and smooth articulation
• Precision CNC machined 6061-T6 aluminium housings and spacers for a secure press fit and long life
• Knurled outer housings to lock firmly into the OE arm
• Offset spacer system for simple caster adjustment without replacing arms
• Made in the USA and supplied as a matched left and right pair

We have run this kit on our own cars and customer builds with outstanding results. Drivers consistently report crisper steering, better braking feedback and a more connected front axle. It is a favourite for track day setups, drift cars and high performance road builds.

Compatibility

Installs in the front tension strut, also known as the radius arm or thrust arm, on the following models:

• BMW 1 Series E82 and E88 - M and non-M
• BMW 3 Series E90, E91, E92, E93 - M and non-M
• BMW F80 M3
• BMW F82 and F83 M4
• BMW F87 M2

Not suitable for xDrive or other all-wheel-drive models.

What is included

• Two press-in spherical bearing housings with 1 inch FK bearings and offset spacers - sold as a pair
• Original arms are not included

Installation

Press tools and a professional alignment are required after installation. For fitting, we recommend MJ Modifications in Warwickshire. Request a quote at info@mjmodifications.co.uk.

Download the official SPL installation guide

Key details

• Part number: SPL CRB E9X
• Bearing: FK 1 inch spherical with self lubricating Teflon liner
• Material: 6061-T6 aluminium housings and spacers, CNC machined
• Adjustment: Caster altered via offset spacers
• Origin: Made in the USA

Search-friendly terms

BMW front radius rod bush upgrade, BMW E90 E92 front lower arm rear bush, E82 E88 1 Series thrust arm spherical bearing kit, E9X caster correction bushings, F80 M3 front arm spherical bearings, F82 F83 M4 front suspension solid bush, F87 M2 front control arm rear bush upgrade, BMW front wishbone bearing conversion, tension strut solid bush kit, BMW front alignment caster adjustment, track day front suspension upgrade, performance front arm bearings.