Parts replaced:
Shift Shaft Seal
Output Shaft Seal
Transmission Mounts
Shift Lever Bushing
Shifter Bearing
Shift Rod Circlip
Selector Rod Washer
Shifter Arm Bushing
Sachs Clutch Kit
Clutch Pivot Fork
Fork Pivot Pin
Clutch Release Arm Spring
Clutch Slave Cylinder
Drive Shaft Flex Disc
Engine Mounts
Driveshaft Center Support Bearing
Oxygen Sensor

With 75K miles on the odometer, the original clutch still felt good on the M Roadster and could probably last at least another 25K miles. But since I’m overhauling the car and I needed to change the seals on the transmission, I might as well go the extra step and replace the clutch as well. The cost of a clutch service at the dealer or even an independent mechanic can easily exceed $1,500, especially once you consider all of the other work you should perform while you’re in there. But if you can perform the service yourself, you’re only paying for the parts, which are actually not that expensive.  Another benefit for doing the work yourself is that you can take your time, get a few other unexpected jobs done while you’re in there and then spend a little extra time cleaning and detailing the space.

I purchased my OEM replacement SACHS clutch kit and transmission parts from FCP Euro. I’ve used racing clutches and lightweight flywheels before, but for the purposes of this car (daily driving), OEM was the way to go. Along with the clutch service, I also planned to replace all of the shifter parts that can wear out. Many of these parts are small plastic items that can usually only be purchased through the dealer, but FCP Euro conveniently had them all online and at competitive prices. Some of the parts are so small, you would think they would be insignificant, but every little piece makes a difference to the feel and performance of the shifter assembly once combined together and put under load. While the transmission was out I would also replace the leaking shifter seal, which is a very common replacement with cars of this age. The seal is only a few dollars but a dealership would charge a few hundred dollars just for the labor, so doing this service yourself is very cost effective. Lastly, I needed to replace the driveshaft coupling and center bearing. The coupling had visible cracks, but the bearing looked fine. I decided to replace it anyway as a preventative measure since getting to it is not easy.

While the transmission would be out, I would also replace the engine mounts and a faulty O2 sensor, since these would be easier to change at that time. The engine and transmission mounts are yet another item that often go overlooked, but can make a huge difference to driving feel and performance. My car’s engine mounts showed only little signs of wear, but after this many years and miles, I knew they were tired and installing new units would make a significant improvement to how the car felt under acceleration and shifting.

Performing the clutch service does require the car to be off the ground and although a mechanics lift would be the best method to do this, you can also use jack stands if you’re really pressed. The process for removing the transmission on the M Roadster is not much different than the process of most BMWs. It is a major job, but just about any novice weekend mechanic can get it done. Much like the suspension, there are a number of resources available that detail the process and you really don’t need any specialty tools to perform the task.

While my transmission was out, I lightly resurfaced the flywheel, replaced the clutch slave, degreased the transmission and pressure washed the undercarriage of the car. All these things help ensure the car will run at its best for a very long time.

Once the job was done and all of the bolts were double checked, it was time for a test drive. The difference of having new shifter parts, a new clutch and clutch slave, plus new bushings, coupling and center bearing were immediate. The car ran very smooth, shifted precisely and simply felt like a brand new car.