Cardan shaft specifications (BMW 5 Series E12)

The cardan transmission consists of two tubular shafts with an intermediate support attached to the body bottom, mounted on a ball bearing. The front cardan shaft is attached to the gearbox flange via an annular elastic coupling.

Length of front and rear propeller shafts up to 1977 model year

* Lengths "a" and "b" are shown in the figure.



Lateral clearance between the splines of the front propeller shaft and the sliding clutch when measured at a radius of 30 mm, mm: 0+0.03.

Axial free travel of universal joint crosspieces, no more than, mm: 0.03.

The greatest permissible dynamic imbalance when measured at the ends of the shaft tube at a rotation speed of 3000 rpm, gf cm: 15.

The greatest permissible dynamic imbalance when measured at the center of the shaft tube at a rotation speed of 3000 rpm, gf cm: 20.



Maximum permissible shaft speed, rpm: 6500.

Preload of intermediate support towards the front of the vehicle, mm: 2.

Intermediate support ball bearing brand: 6006 2 RS.

Since model year 1977 on BMW "525", "528" and "528i" was equipped with a cardan transmission with a ring elastic coupling on cars with a manual transmission and with a segment elastic coupling on cars with an automatic transmission.

Features of the characteristics of cardan shafts

Tightening torques of main threaded connections, kgf·m

• Nut of the bolts for fastening the ring elastic coupling: "518", "520", "520i": 6,8-7,5; "525", "528": 10,5-11,8.
• Nut of the hinge disc mounting bolt: 10.5-11.8.
• Clamping sleeve: 4.0.
• Nuts for the bolts securing the intermediate support crossmember to the body bottom: 2.2-2.4.
• Nuts for the bolts securing the propeller shaft flange to the rear axle gearbox flange: 6.8-7.5.

Since model year 1977

• Elastic coupling mounting bolt nut:
• on vehicles with manual transmission (M12x1.5): 11.4-12.7;
• on cars with automatic transmission: 11.4-12.7.
• Nut for bolts fastening the cardan shaft flange to the gearbox flange (M10): 6.8-7.6.
• Nuts for the bolts securing the intermediate support crossmember to the body floor (M8): 2.2-2.4.
• Nuts for the bolts securing the intermediate support heat shield: 1.2-1.4.

Since 1980 model year

• Nuts for fastening bolts of segment elastic coupling: M10: 6.8-7.6; M12 11.5-13.0.
• Clamping sleeve: 4.0-4.5.
• Front propeller shaft fork mounting nut (M12): 9.5-10.5 (first apply a special adhesive such as Loctite to the threaded end of the shaft).