Upgrading the differential in a Bmw E60 535xd can significantly enhance traction and handling. This article outlines the process of swapping the stock open differential for a limited-slip differential (LSD) using an E65/E66 differential as a base. This modification focuses on improving performance by ensuring power is distributed effectively to both rear wheels, especially during cornering and acceleration.
Choosing the Right Differential for a BMW E60 535xd
The project began with a 2009 BMW 535i equipped with aftermarket bolt-ons and KW V3 coilovers. The initial goal was to enhance suspension performance with rear monoballs and polyurethane differential/subframe bushings. However, it was decided to install a helical LSD while the subframe was already removed. This proactive approach minimized downtime and labor costs.
A key component of this upgrade was sourcing a larger case differential from an E65/E66 7 Series. This differential, with a 3.38 final drive ratio, offered a close match to the factory 3.46 ratio (a 2.3% difference), minimizing impact on speedometer accuracy and overall drivability. The E65/E66 differential’s bolted ring gear design and compatibility with the E60’s subframe geometry made it a virtually plug-and-play solution, even allowing the use of the existing driveshaft.
Installing the LSD and Upgraded Components
The selected LSD was an MFactory helical unit, known for its smooth and predictable power transfer characteristics. To accommodate the increased torque capacity of the LSD, upsized 38mm axles from a manual transmission/diesel model were also installed. These robust axles provided additional strength and reliability to handle the enhanced traction.
The installation process included replacing the factory differential and subframe bushings with polyurethane units. While these stiffer bushings improve handling precision, they also made reinstalling the differential into the subframe more challenging.
A notable challenge encountered during the process was a seized driver-side axle, requiring significant effort to remove. This highlighted the importance of thorough preparation and anticipating potential issues when working on older vehicles.
Achieving Enhanced Traction with the BMW E60 535xd LSD Upgrade
With the new LSD and upgraded components installed, the BMW now benefits from significantly improved traction. The helical LSD ensures power is consistently delivered to both rear wheels, minimizing wheel spin and maximizing grip. This results in enhanced acceleration, improved cornering stability, and a more engaging driving experience. This upgrade transforms the driving dynamics of the BMW, providing confident handling and predictable power delivery in various driving conditions.
