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.
We offer front and rear axle shafts for your BMW. BMW all wheel drive models front axle shafts are common failure items. We recommend inspecting the rubber boots regularly as a preventative measure. If the CV joints of the axle shaft are exposed to water and dirt they are very likely to fail prematurely.
These heavy-duty clutch kits use aluminum lightweight flywheels with sport clutch components to give your clutch the grip and clamping force it needs to cope with high torque upgrades. Our kits were developed through racing programs by companies affiliated with our own race team - JB Racing, Sachs Sport, OS Giken, and UUC Motorwerks. JB Racing is the leader in aluminum lightweight flywheel upgrades. They are direct replacements for the stock dual-mass flywheels with steel contact surfaces and computer balanced to 14,000 RPM. JB has partnered with Sachs to spec sport/HD clutch discs and pressure plates that work seamlessly with their aluminum flywheels. The result is a clutch/flywheel upgrade package that functions a lot like the original clutch combo with near-stock levels of effort and engangement but with a much higher torque capacity. Don't let the clutch be your weak link in a highly tuned car!
Upgrading various parts of the differential can have tremendous benefits in your car's performance. It's easy to forget that the differential is a source for making your car faster and handle better so it's often overlooked. The engine is not the only place to make the car faster. Our differential options vary from gearing upgrades to limited slip conversions. You can purchase the ring & pinion gear sets on their own (professional installation required) or have us build a diff around your own specifcations. The options are almost endless! Every custom-built diff is fully rebuilt with seals and bearings. We also design and supply bushing options to reduce driveline wind-up, finned differential covers for better cooling, and more!
Ratio Changes - Changing the differential gearing is one of the best and most-effective upgrades you can make on any BMW (old or new). By using a shorter (numerically higher) final drive ratio you are increasing your RPM relative to road speed - this puts you in a more powerful RPM range than before! Since you're in a 'meatier' part of the power band you're now putting down more power/torque to the ground. If you can trade outright top speed for faster acceleration at daily speeds then this is the perfect upgrade for you.
Limited Slip Upgrades - Sadly, many BMWs today are not equipped with a limited slip (posi-traction) differential. BMW has tried to compensate by using traction control that cuts power at the engine or applies the brakes to retard wheel spin (or a combination of both). But nothing beats the function and feel of a a true LSD which may be why BMW continues to use them in M cars. Our LSD upgrades can be done a number of different ways - a factory-type limited slip unit with either 2 or 3 clutch packs, helical type, OS Giken unit, or something truly custom. We can also vary ramp angles and setup to change the limited-slip behavior under acceleration, deceleration, and cornering. Need a custom diff? Call or e-mail to have a quote.
Got a vibration through the driveline on your BMW? Did you know that the u-joints are not replaceable on a factory driveshaft? Our remanufactured driveshafts allow for future replacement of u-joints and are rebuilt to a higher specification than the factory driveshaft. We start with OEM u-joints and then machine yokes onto the driveshaft to allow for future u-joint replacement. All bushings, universal joints, center bearings are replaced with new hardware (flex discs are not included but available separately). The whole unit is then dynamically balanced on a precision Axiline Balancer.
From the factory, engine and transmission mounts are rubber and thus a wear component. Worn out engine or transmission mounts create sloppiness and a disconnect between the driver and your BMW's powerplant. If your vehicle is purpose built for the track, we recommend solid engine and transmission mounts. These have zero deflection, but come at the expense of added NVH (noise, vibration, and harshness). Poly engine and transmission mounts offer a good balance between OEM rubber and solid mounts for those with mixed purpose vehicles, offering great performance and connection with little sacrifice in terms of NVH.
Servicing the driveshaft, axles and related components is key to maintaining a smooth and balanced driving experience. Certain components require the use of specific specialty tools and you can find them here.
There's nothing worse than a sloppy shifter in your manual transmission BMW. For most applications, we have poly and teflon rebuild kits available to make your shifter feel more precise than it did the day it rolled off the showroom floor. Don't underestimate the value of a good shifter rebuild, this will restore the engaging driving experience that makes your BMW the ultimate driving machine.
Looking for parts for your BMW automatic transmission or manual transmission? You'll find many of the parts available to service your BMW's transmission here. While internal transmission servicing and rebuilding should be done by professionals, there are a lot of things on the outside of the transmission that you can service or replace yourself. These include gearbox seals, o-rings, gaskets, automatic transmission filters, backup light switches, mounting bolts, flanges, collar nuts, screw plugs, Mechatronics, and more.
Keeping drivetrain fluids fresh and in proper service is paramount to maintaining your BMW properly. Typical service intervals range anywhere from 60-100k miles.
When wheel bearings begin to fail, you will normally experience symptoms of a squeaking or grinding noise, often accompanied by slight vibration in your steering wheel. Once your diagnosis is complete, we recommend replacing as soon as possible to prevent damage to your hub or steering issues. We offer OE brands and Genuine BMW wheel bearings, to ensure that you donât have to do the job twice.
