BMW Self Adjusting Clutch – SAC – DIY – How To Replace
Since the early 2000s BMW has been using a clutch design known as the Self Adjusting Clutch. The pressure plate in this clutch design employs a mechanism that allows the friction surface of the assembly to adjust to the clutch disc’s thickness and position. In other words, as the clutch disc wears and becomes thinner, the pressure plate adjusts it’s static position to compensate for the clutch disc wear, as well as compensate for inconsistencies in the mating surface of the dual-mass flywheels. This is intended to keep the clutch pedal at a common engagement point in it’s travel, through the life of the clutch and attempt to reduce disc wear.
The self adjusting clutches require a unique installation procedure. If the proper procedure is not followed, during installation, the clutch assembly will not operate properly. This typically results in a clutch that will not release once everything is reassembled. Follow along, below, as we outline the proper self-adjusting clutch assembly steps. These steps MUST be followed exactly as shown. Additionally, the pressure plate lock must not be removed prior to the full installation of the disc and pressure plate assemblies. Any deviation from these guidelines will result in a damaged, and useless, pressure plate assembly.
The installation of a self adjusting clutch requires a special clutch alignment tool. This is due to the pressure plate lock preventing the use of a standard alignment tool.
Here, we’ll show you the basic assembly of the self adjusting clutch. We will not be actually installing the clutch. Therefore, we will not remove the pressure plate lock.
(click photos to enlarge)
1) Install flywheel and pilot bearing as you normally would.
2) Install clutch disc with plastic (forward) section of alignment tool.
3) Install the pressure plate and torque to specs.
4) Remove the pressure plate lock.
***** Once lock is removed DO NOT loosen any of the pressure plate bolts.
Doing so will damage the pressure plate and it will be rendered useless. *****
5) Thread bolt into the forward section of the alignment tool and pull the tool from the clutch assembly.
Click below for clutch parts and installation tools:
(click below then ID your BMW model and search “clutch”)