Turner Motorsport BMW Drivetrain Parts

Designed for track drivers, drift enthusiasts, and drag racers alike, this all-in-one driveline upgrade eliminates the factory weak points and reinforces your drivetrain for high-performance abuse. Whether you're laying down 500HP, clutch-kicking through corners, or launching hard at the strip, this cover keeps your differential secure, cool, and ready for battle.

The stock E30 differential cover features a single mounting provision—fine for a stock M20, but guaranteed to fail on your boosted high-horsepower M5X build. After years of broken covers, mounting tabs, and dreams, our team of E30 enthusiasts engineered the ultimate fix.

Unlike the brittle OEM cast aluminum cover, our upgraded differential cover is CNC-machined from 6061-T6 billet aluminum, offering a 30% increase in material strength alone. More importantly, a secondary mounting ear has been integrated into the design for added support, drastically improving stability and driveline shock absorption. The secondary mount is tied into the chassis using a reinforced sheet metal bracket and a billet aluminum plate, allowing for bolt-on installation or welding for ultimate rigidity.

Another major flaw of the factory E30 differential cover is its lack of any cooling provisions, leading to overheated fluid and premature wear. Our engineers solved this issue by incorporating advanced cooling features into the design. Large external fins have been added to the cover, and are optimized using CFD (Computational Fluid Dynamics) analysis to efficiently dissipate heat, reducing overall fluid temperatures. By maintaining a more stable differential temperature, this cover ensures consistent performance and extends the lifespan of your differential fluid. A built-in air duct assists in cooling by increasing airflow around the differential, further preventing heat-related failures. Our cover features optional -6AN fittings, allowing for easy integration of an external fluid cooler if desired. Finally, a 1/8 NPT port is included with the kit to ensure compatibility with fluid temperature monitoring systems.

Precision-machined from 6061-T6 billet aluminum and finished with a black hard coat anodizing, this cover is built to withstand hard use. Despite its robust construction and superior durability, this differential cover retains factory mounting features. This means any E30 188mm differential cover bushing can be installed, allowing you to tailor our upgraded cover to your build. The cover also accommodates large rear sway bars, ensuring fitment on cars with upgraded suspension. Our proprietary removable air duct provides easy access to sensor bungs, fill plugs, and drain plugs, making differential service a breeze.

FEATURES

Unmatched Strength & Durability - Heavily reinforced mounting locations are designed to withstand extreme horsepower, torque, and shock load. Secondary Differential Mount - A built-in secondary mount, integral sheet metal bracket, and billet adapter plate make this the strongest E30 differential cover on the market. Bolt-On or Weld-On Installation - The secondary mount is designed for easy bolt-in installation or can be welded to the chassis for ultimate rigidity. Optimized Cooling - Large external fins, designed using CFD analysis, dissipate heat efficiently, reducing overall differential fluid temperatures. Integrated Breather System - An integrated breather system reduces internal cavitation by properly venting built-up pressure. Enhanced Fluid Management - Includes a 1/8 NPT sensor port for real-time fluid temperature monitoring, and optional -6AN fittings for adding an external fluid cooler. Aerodynamic Air Duct - The included aerodynamic air duct further reduces fluid temperatures, increasing fluid service life and reliability. KIT CONTENTS

Dual Mount Differential Cover Assembly Includes the cover, sheet metal mounting bracket, billet aluminum mounting plate, and aerodynamic air duct. Installation Hardware Kit Includes everything you need to install this masterpiece on your E30! Differential Gasket Choose between a Genuine BMW paper gasket or make your own gasket with Loctite 5970. Optional -6AN fittings (2) for adding an external fluid cooler. Differential Cover Bushings Choose between Powerflex, OE MOOG, and Genuine BMW, or add your own (two E30 188mm differential cover bushings required for installation). Gear Oil Choose between Liqui Moly, Redline, and Genuine BMW, or supply your own fluid for reassembly.

Harness unused potential. Drive with confidence. Engineered to maximize strength and cooling performance while utilizing the unused secondary factory differential mount for enhanced support and driveline stability.

Our Turner Motorsport Dual-Mount Differential Cover is purpose-built to reinforce one of the most critical components in the G8X M3/M4 drivetrain. From the factory, BMW includes a secondary bushing location in the rear subframe but leaves it unused. Our solution fully capitalizes on this overlooked feature, giving the differential a second point of support for improved rigidity, reduced movement, and enhanced driveline response under load.

This cover is more than just a mounting upgrade. It’s precision-machined from 6061-T6 billet aluminum for exceptional strength without unnecessary weight. An aggressive fin profile improves thermal efficiency, helping to lower fluid temperatures in high-stress environments. Inside, the cover features an embossed channel that mirrors the ring gear path, ensuring fluid stays in contact where it's needed most, improving cooling and lubrication in all conditions.

Whether you're carving corners on the street or pushing the limits on track, this differential cover is designed to keep your rear end cool, stable, and responsive.

Key Features and Benefits:

The dual-mount design utilizes the factory-provided secondary bushing location, adding critical support to reduce differential deflection, extend bushing life, and minimize wheel hop.
CNC-machined from 6061-T6 billet aluminum, offering high strength and a precise fit.
Built-in cooling fins increase surface area for improved heat dissipation and lower differential fluid temperatures.
Internally contoured to follow the ring gear profile, promoting consistent fluid coverage and effective lubrication.
Maintains a 1.1-liter fluid capacity, closely matching OEM specifications for ease of servicing.
Integrated -6 AN ports support the addition of an external differential cooler for increased fluid volume and extended service intervals.
Compatible with the factory differential fluid temperature sensor and includes provisions for 1/4” NPT aftermarket sensors.
Product Development:

Like all Turner Motorsport performance solutions, this differential cover was developed in-house by our dedicated Research and Development team. Designed, engineered, tested, and quality-inspected using advanced tools including FARO laser scanning for reverse engineering, SolidWorks 3D CAD modeling, in-house rapid prototyping, and extensive long-term testing, you can trust that this part meets the highest standards of fit, function, and durability.

From spirited street driving to full-throttle track days, the Turner Motorsport Dual-Mount Differential Cover ensures your G8X delivers the response, strength, and cooling capacity it needs when it matters most.

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

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 our diff cover can handle anything you throw at it. Not only is it an absolute masterpiece to look at but the billet diff cover checks all the boxes for features needed. Reinforced mounting ears for strength and stability, never again will you break an ear off your diff cover like the factory units are known to do. Each ear is not only unified with the one-piece billet cover but also feature 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 to 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 mounting surface was designed to be compatible with both the OEM gasket or RTV of your choosing, some people don't trust the gaskets and we get it. You can transfer your speed sensor directly to your upgraded billet cover and it even features a provision for the sensor wire mounting. Factory bushing geometry allows you to use any E36 diff busing including rubber, poly, and even solid mounts. 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 also be used for expanding to 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.

Why the upgrade?

If you're new to differential covers used in earlier generations like the E30, you'll find significant improvements in the OEM E36 cover. Unlike the E30's single mount design, the E36 features a dual mount design, which was introduced to address common issues such as broken mounts due to worn-out bushings and aggressive driving. This upgrade significantly enhanced durability and reliability.

While the factory E36 differential cover was a significant improvement with its dual mounts compared to the previous generation, there are still some shortcomings that the original cover doesn't address. Most factory differential covers, including those on the E36, are cast from aluminum. However, due to the porous nature of cast aluminum, the mounting ears on these covers cannot withstand the intense shocks typical in motorsport or in vehicles with significantly increased power.

Upgrading to our Reinforced 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 boasts a visually appealing design.

Key Benefits:

Reinforced mounting ears for strength and stability - never again will you break an ear off during an aggressive drive or track event
External fins on the back side, bottom, and mounting ears 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:

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 including the use of the OEM gasket
Factory geometry bushing size for use with OEM and aftermarket poly bushings
Removeable air duct for easy access to sensors and drain/fill plug
Retains OEM speed sensor and wire mount location
Product development:

Our Reinforced Billet Diff Cover was designed, engineered, tested, and quality inspected by our Research and Development team at Turner. Nothing but the highest level of precision and quality through leading-edge product development technology including FARO laser scanning for reverse engineering and quality inspection, SolidWorks 3D CAD modeling, rapid prototyping utilizing our in-house 3D printer, and rigorous long-term product testing.

The ULTIMATE shifter upgrade for your BMW! Experience more precise throws, less shift lever travel, and an all-around transformation in your shifting experience.

For dozens of years, enthusiasts have critiqued the imprecise and vague feeling of BMW manual transmissions. Plagued with long throws, fore and aft play in gear, and a generally loose feeling, your OEM BMW shifter leaves much to be desired. While most standard carrier-mount short throw shifter kits will aid in reducing throw length and eliminating side-to-side play in gear, some enthusiasts long for a hardcore, race-inspired shifter that completely removes play and excessive throw length. At Turner Motorsport we share the same desire and set out to offer the ULTIMATE upgrade with this Performance Chassis Mount Short Shifter.

WHY UPGRADE?

Factory BMW shifter assemblies are complex by nature. The main component of this assembly is the shift carrier, a cast aluminum piece positioned inside the transmission tunnel that incorporates bushings at both ends for mounting. Like most factory parts, these bushings are designed to reduce NVH (noise, vibration, and harshness) transmission to the cabin. To the spirited driver, however, these bushings translate to flex and vagueness in the shift lever. Moreover, because this carrier is mounted to both the transmission and the body, the entire shifter assembly will "float" with the driveline, further increasing the vague and imprecise feeling of your shifter.

Our Performance Chassis Mount Short Shifter removes the shift carrier assembly entirely—removing any prospect of flex caused by bushings or driveline movement. By contrast, this chassis mount shifter offers a drastic reduction in shift lever travel, vagueness, and side-to-side play. An elevated base allows for moving the fulcrum point upwards, resulting in a much shorter and more precise throw. Shift times are further reduced by a tall, "rally style" shift lever, used to aid in leverage while also bringing the lever closer to the steering wheel. Our design incorporates a proprietary centering spring design, which is adjustable for increasing or decreasing self-centering force. In short, this design eliminates all the drawbacks of your factory BMW shifter, translating to more control, greater precision, shorter throws, and faster shift times.

FEATURES & BENEFITS

Reduced Throw: Modified shifter geometry and heightened fulcrum point translate to a shorter shift lever throw
Improved Shifter Feel: Eliminating the shift carrier and associated bushings drastically reduces "slop" and side-to-side play in the shift lever
Increased Precision: Mounting the shifter to the chassis allows for little to no variation in gear selection
Universal Fitment: Fits many BMW chassis with the provided base plate and hardware (see "Fits These Cars" for exact fitment information)
DESIGN

6061 aluminum, 4130 steel, and 316 stainless steel construction
A type-II black anodized finish
Adjustable self-centering spring
"Rally Style" shift lever
Spherical bearing pivot with maintenance-free brass insert
Product Development:

Our Chassis Mount Shifters are designed, engineered, tested and quality inspected by our Research and Development team at Turner. Nothing but the highest level of precision and quality through leading-edge product development technology including FARO laser scanning for reverse engineering and quality inspection, SolidWorks 3D CAD modeling, rapid prototyping utilizing our in-house 3D printer and rigorous long term product testing.

Rubber engine and transmission mounts for a street car and solid aluminum for the track, right? Well, it's not that straightforward anymore.

Stock rubber fluid-filled mounts are designed to be soft and comfortable, limiting the NVH (noise, vibration, and harshness) felt by the driver. The drawback inherent with a conventional design is driveline deflection, making it more difficult to put the power to the wheels, as well as making a money-shift or miss-shift more likely as they age. Solid mounts are exactly the opposite of this - they permit tons of NVH while offering zero deflection, making these a must have for track-driven vehicles looking to capitalize on every ounce of performance available. Enthusiasts looking to find the best of both worlds often look to polyurethane engine mounts - and many are disappointed with other designs on the market. Seeking a mount that offers a positive connection yet doesn't deform, fail, or rattle the fillings out of their mouths is frequently a lost cause.

Until now. 

We engineered these mounts with these very concerns in mind. We know if a soft mount offers a sloppy connection it doesn't work on the track, and a solid mount isn't acceptable as a daily driver (for most!) and set out to engineer a mount that would meet the needs for both. At the core of our enclosed design is a partially-constrained, multi-piece polyurethane bushing with precisely-set preload. This architecture absorbs and disperses resonant engine frequencies as opposed to amplifying them (like some other designs do), which results in a positive-connection, enthusiast-feel mount with the vibration. Understanding that heat is a concern for the passenger side mount's close proximity to the exhaust, we utilize a PEEK thermal insulation plate to greatly reduce heat transfer to the polyurethane, making heat a non-issue for these mounts. 

We offer two durometers, with both densities offering similar "positive connection" feeling. 60A is slightly softer and offers more of a stock feel, while 80A delivers a little more engine "feel" while under acceleration. 

Product features and benefits:

• Crisper throttle response, positive shifter location, direct power transfer
• High quality polyurethane offered in both 60A & 80A durometers (rebuildable, too)
• Resistant to water, ozone, and chemicals, maintaining its resiliency and elasticity longer than conventional rubber.
• Precision machined billet 6061-T6 aluminum housing, black anodized for durability and corrosion resistance. Grade 10.9 stud - fear not, big turbo owners.
• Thermal isolation spacer on the hot side to resist heat transfer into the poly
• Engineered in-house and made in America

This item fits the following BMWs:
2008-2013 E82 E88 BMW 128i 135i 1M Coupe
2006-2011 E90 BMW 325i 325xi 328i 328xi 330i 330xi 335d 335i 335xi - Sedan
2007-2011 E91 BMW 325i 325xi 328i 328xi - Touring Wagon
2007-2013 E92 BMW 328i 328xi 335i 335is 335xi - Coupe
2007-2013 E93 BMW 328i 335i 335is - Convertible
2009-2016 E89 BMW Z4 sDrive30i Z4 sDrive35i Z4 sDrive35is

Lightweight single mass flywheel paired with the Sachs clutch kit, perfect for naturally aspirated M20's! Fits early and late model cars.

A perfect upgrade and refreshment for your M20! Free up lost horsepower with the lightened single mass flywheel and get back the life in your clutch pedal. This kit is put together with the idea of an OEM+ upgrade, perfect for people looking to refresh the driving experience of their M20 and get back the full potential of this tried and true motor.

This kit includes everything you need to do the clutch and flywheel service on your M20. While you're in there it is a good idea also to purchase the common transmission seals, fluid, and mounting hardware which are listed below.

Clutch Kit:

Sachs OE replacement clutch disc - 21211223097
Sachs pressure plate - 21211223026
Sachs 323 throw-out bearing (taller bell housing/ETA models) - 21511204525
Pilot bearing - 11211720310
Turner Single-Mass Flywheel:

Lightweight flywheel for quicker, effortless revs that improve throttle response and free up lost horsepower. Tested and approved by the engineering team at Turner Motorsport, tested in early, late, ETA and IS model E30s for confirmed fitment.
Fits shallow and deep bell housing transmissions
Ring gear suited for both starters (P# 12411726504 + 12411361874)
Heavier than other lightweight flywheels, and lighter than OEM, it's like the Goldie Locks of flywheels - it's just right
Reference pin for bell housing crank sensor
Strong Single-Piece 4140 HT Steel construction
Designed to be used with factory and OE clutches
Weight savings between 5-14lbs depending on your OE flywheel

Components strongly suggested while your transmission is out of the car.:

Transmission Seals Kit - T#29898446
Fluid - 75-90 or preferred fluid type (approximately 1.25 liters)
Transmission Mounting hardware - T#30197962

Used when retrofitting an OEM or aftermarket CSL intake on a vehicle with SMG transmission.

Its no secret the CSL intake plenum is the pivotal upgrade for your S54. If you are fortunate enough to have an SMG equipped vehicle you are going to need a bracket to relocate the expansion tank. Our Turner motorsport bracket fits perfectly with the engine bay to facilitate the installation of your genuine or Turner branded CSL intake plenum.

Design:

Direct fit, perfect OEM replacement
304SS sheet metal design, engineered to be simpler and cheaper than its formed OE counterpart
Reverse engineered with FARO laser scanning and Solidworks CAD technology

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