SPL Parts BMW E9X/E8X/F8X (1/3 Series, M2/M3/M4) Front Caster Rod Bushings - Tension Strut/Thrust Arm - Non-Adjustable Spherical Bearing Pair

SPL Parts radius arm monoball bearings for BMW E8X E9X F8X platforms

Transform front end response on your BMW with this fixed-geometry monoball conversion from SPL Parts. By replacing the soft hydraulic bush in the forward lower arm with a 1 inch motorsport spherical bearing, you remove unwanted compliance that causes vague steering, brake shimmy and alignment change under load. The result is crisp turn in, rock solid braking stability and repeatable handling on fast road and track days.

We run this kit on our own cars and customer builds. The improvement in steering precision and driver confidence is immediate. Feedback from owners has been consistently positive for durability and on-road feel.

Why upgrade to a monoball radius arm bearing

• Locks down toe and caster movement under braking and cornering for laser sharp steering
• Reduces brake judder and front end shimmy caused by OEM bush deflection
• Delivers consistent geometry through bumps, kerbs and heavy load
• Fixed geometry design maintains factory alignment settings while adding motorsport precision
• Ideal for performance road cars, track day builds and time attack setups

Engineering details

• 1 inch FK spherical bearings with self lubricating PTFE liners for low friction and long service life
• CNC machined 6061 T6 aluminium housings with knurled outer surface for a secure press fit
• Low maintenance, high durability construction for repeatable performance
• Made in the USA
• Sold as a pair
• Part number: SPL CRBN E9X

Vehicle fitment

Front forward lower arm bearing kit for the following rear wheel drive BMW models:

• E82 E88 1 Series. M and non M. 2008+
• E90 E91 E92 E93 3 Series. M and non M. 2006 to 2013
• F80 M3. 2014+
• F82 F83 M4. 2014+
• F87 M2. 2016+

Note: Not compatible with xDrive or AWD models.

Installation and support

Professional fitting recommended. We offer installation at MJ Modifications in Warwickshire. Request a fitting quote at info@mjmodifications.co.uk.

Installation guide: Download SPL CRBN E9X installation PDF

Brand

SPL Parts

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