The Schaeffler Gruppe’s (www.schaefflergroup.com) INA and FAG brands have developed powertrain and chassis-based bearing solutions that are said to provide marked improvements in vehicle fuel economy and emission levels with little change to current production vehicle and engine designs. A new “twin tandem” 4-row angular contact ball bearing solution for SUV and light truck wheel-hub assemblies has reduced fuel consumption and CO2 output by as much as 1.5% (10.6 gal. and 149 lbs. of CO2 per year), according to Schaeffler. The design replaces each row of tapered rollers with two ball rolls, creating a 4-row ball system that eliminates rib friction and bearing friction by as much as 50%, resulting in a lower operating temperature and increased service life of bearing lubricants. The design is engineered to replace existing wheel hub assembly systems, thereby reducing the need to reengineer the vehicle hub system and limiting changes to existing manufacturing processes.
Further fuel savings have been discovered on the powertrain side by replacing traditional plain bearing camshaft configurations with needle bearings, which have better friction characteristics. In one test involving the replacement of six plain bearings on two overhead camshafts, fuel consumption was reduced by 0.5%. Further, the company says its tests prove there were no changes to the acoustics of the engine by modifying the bearings. Schaeffler says it has a number of projects under way to provide rolling bearing cam shaft solutions to some of its European OEM customers in the medium-term.