Turner Motorsport BMW Drivetrain Parts for BMW E90 M3 S65 4.0L

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Building your perfect BMW is more than just adding horsepower and stiff suspension. Your drivetrain needs attention in order to deliver power effectively. Most BMWs feature comfortable clutch discs, heavy flywheels, long shifter throws, and open differentials. The drivetrain transmits power to the wheels, but can also be a source of power loss when it is designed for comfort rather than performance. Everything on this page will help you improve your power delivery and driving experience by providing custom Limited Slip Differentials, Short Shift Conversions, Performance Clutch Discs, Lightweight Flywheels, and anything else your BMW needs to be the perfect driving experience.

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Turner DSSR - E9X M3 (111.7mm)
affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
Turner Motorsport - Corporate Logo
T#:2973566
Part#: 017358LA01
In Stock
Sale - Save 25% $ 208.99

This product was last offered at the strikethrough price on
06-14-2026

$ 156.74 USD
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Sale - Save 25%
$ 208.99

This product was last offered at the strikethrough price on
06-14-2026

$ 156.74 USD
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BMW E9X Ultimate Shifter Rebuild & Upgrade Kit
affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
Turner Motorsport - Corporate Logo
T#:5858437
Part#: E9XM3USRKT
Ships in 1-2 days
Sale - Save 25% $ 565.99

This product was last offered at the strikethrough price on
06-14-2026

$ 424.51 USD
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Sale - Save 25%
$ 565.99

This product was last offered at the strikethrough price on
06-14-2026

$ 424.51 USD
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Includes everything necessary to eliminate shifter and driveline slop, including a Turner DSSR, Turner Shifter Arm Bushing, & ECS Teflon Shifter Bushings
Upgraded Billet Differential Cover - E82 1M, E90 E92 E93 M3
affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
Turner Motorsport - Corporate Logo
T#:32350852
Part#: 049395LA
Ships in 3 Business Days
Sale - Save 3% $ 1,128.99

This product was last offered at the strikethrough price on
06-14-2026

Starting at $ 1,095.12 USD
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Sale - Save 3%
$ 1,128.99

This product was last offered at the strikethrough price on
06-14-2026

Starting at $ 1,095.12 USD
Free Shipping

Single piece 6061 construction, optimized cooling, provisions for temp sensor, and external cooler with removable air duct.

Built to last, made from a single piece of 6061 billet aluminum with a rugged and good-looking hard-coat anodizing the Turner diff cover can handle anything you throw at it. Not only is it an absolute masterpiece, but this billet diff cover checks all the boxes for features needed. Reinforced mounting ear for strength and stability. The mounting ear is unified with the one-piece billet cover and features added material for the highest durability possible. This diff cover is cool, literally, the entire construction was designed with optimized cooling in mind. External fins are strategically placed on the rear face, bottom, and between the mounting ears of the cover, serving as effective heat sinks for optimal heat dissipation. This ensures stable temperatures, promoting longevity for both the fluid and your differential. Additionally, the internal design ensures continuous oiling and lubrication of the ring gear, maintaining its stability and preventing fatigue by controlling heat more effectively. An internal baffle at the cover's corner helps maintain proper pressure and prevents cavitation.

All of the OEM features were retained along with the upgrades. The drain and fill plugs on the diff cover are upgraded to -6AN using the provided high-pressure fittings with replaceable o-rings. The drain and fill plugs can now be used for an external oil cooler allowing you to further expand the fluid capacity for optimized cooling and service intervals. To keep an eye on things from the driver seat is 1/8 NPT provision for temp sensors, this product from Turner has you covered at every turn.

Upgrading to our Turner Billet Differential cover gives you the strength you need to push your car to its limits without worrying about snapping a diff mount from clutch kicking or other shocks to the drivetrain. In addition to its enhanced strength, this differential cover includes numerous other upgrades and conveniences. These include improved cooling and lubrication for the ring gear, upgraded fill and drain plugs, and the option to expand an external oil cooler for extreme motorsport usage. Designed to complement both upgraded daily drivers and extensively modified track cars, it also offers a visually appealing design.

Key Benefits:

Reinforced mounting ear for strength and stability
16% Increased fluid capacity
External fins on the back side, bottom, and mounting ear on the casing for maximum cooling and consistent fluid temps
Removeable air duct to direct air across the cooling fins for even more temperature control
Optimized internal design to keep fluid consistently on the ring gear
Integrated breather to prevent cavitation by venting the appropriate amount of pressure being built up in the diff housing
-6AN ports to incorporate the use of a differential cooler - this increases capacity and lowers temps allowing for extended fluid change intervals
1/8 NPT fitting for the use of a temp sensor to monitor fluid temperature
Design:

Fits manual transmission Large Case 215mm differentials
Single piece 6061 Billet aluminum construction
T6 Black hard coat anodizing for superior corrosion resistance and aesthetics
Compatible with most differential coolers(-6AN) and temp sensors(1/8 NPT)
Designed to accommodate oversized rear sway bars
Retains OEM mounting features
Factory geometry bushing size for use with OEM and aftermarket poly bushings
Removeable air duct for easy access to sensors and drain/fill plug

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S65 Lightweight Single-Mass Flywheel - E90, E92, E93 M3
affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms
Turner Motorsport - Corporate Logo
T#:53079373
Part#: 048907LA
In Stock
New Item
Starting at $ 815.99 USD
Free Shipping on orders $49 and up
Starting at $ 815.99 USD
Free Shipping on orders $49 and up

The factory BMW S65 dual-mass flywheel is engineered with comfort in mind, catering to the luxury-oriented expectations of the brand’s driving experience. Its design focuses on dampening drivetrain vibrations, smoothing out gear transitions, and minimizing harshness during operation. However, this refinement costs valuable performance. The dual-mass flywheel adds a substantial 27 lbs of rotational mass to the drivetrain, which significantly hinders throttle response and makes rev-matching feel sluggish and disconnected. Moreover, dual-mass flywheels are notorious for being a weak link in modified or high-performance builds and can prove costly to replace when they inevitably fail.

Our Single-Mass Lightweight Flywheel Conversion addresses all of these shortcomings with a purpose-built, lightweight, single-mass design that prioritizes performance. Weighing in at only 19 lbs., this design significantly reduces rotational mass, allowing your S65 to achieve its true motorsport potential!

Features & Benefits:

Precision machined from 4140 HT heat-treated chromoly steel for exceptional toughness, even wear properties, and increased durability.
Material quality promotes even wear across the entire friction surface, prolonging component lifespan.
Heat treated to HRC 28-32, tempered to relieve stress and improve dimensional stability.
Hardness improves component wear characteristics.
Black oxide coated for corrosion resistance on non-friction surfaces.
Precision balanced to exceed OEM specification (G16 spec to 175g-mm).
Specifically designed to work with S65 OE-architecture clutches.
Optimized step height maximizes clutch clamp load and offers a prolonged service life.
Performance:

8 lbs. lighter than the factory BMW flywheel!
OEM Dual-Mass: 27 lbs.
Turner Motorsport Single-Mass: 19 lbs.
Faster revs
Improved throttle response and acceleration
Allows for a more engaging driving experience and delivers a feeling of direct connection
Installation:

Flywheel Hardware: For added peace of mind, apply Blue or Orange Loctite when installing factory flywheel bolts that do not come with pre-applied threadlocker.

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