BMW 33101214933 Differential

Disconnect the driveshaft from the input flange of the final drive and support the driveshaft with wire. Remove the constant velocity joint bolts and support the halfshafts from the body. Disconnect the speed sensors, if equipped. Support the unit and remove the front mounting bolts, then the rear mounting bolts. Lower the unit. The axle ratio is marked on the housing or cover. To install the final drive, on E30 models, install the front bolts to support, on E36 models, install the rear bolts about 10 turns to support the assembly, then start the rear bolts. On high output engines or if used for sport events install new fasteners. Tighten the bolts as follows: E30 models and M44 Z3 models to 80 ft. lbs. (110 Nm), all other E36 models: Front bolts to 70 ft. lbs. (95 Nm) and rear bolts to 57 ft. lbs. (77 Nm). Install the halfshafts and the driveshaft.

First, check the fluid level, type, and amount. Then, replace the fluid with the recommended lubricant. Additionally, inspect the differential bearings for wear or damage, and remove them to examine the drive and driven gears, replacing any components as necessary.