Final Drive/Differential: Notes
The differential unit 188 L (L = low friction) is used for the first time on the 3 series.
The 188 L differential uses angular-contact ball bearings (1), compared to the linear contact of tapered roller bearings, the point contact of the angular-contact ball bearings produces less friction. By reducing friction the temperature of the gearbox is reduced which in turn increases efficiency.
The differential utilizes a lifetime fill oil.