Seals play an important role in the wheel-bearing system. They keep lubricant within the bearing, they keep contaminants out, and some seals help maintain pressure within a system.
A seal can keep a bearing sealed, but if it creates too much friction, it can hurt fuel economy by increasing rolling resistance. To reduce friction, many seals are using new material and lip designs to seal the bearing.
This video is sponsored by The Pronto Network.