Feature Issue: Wheel Bearing Lubrication

According to Timken, automotive and light truck tapered roller bearings generally use a NGLI No. 2 or No.1 grease. No. 3 and heavier greases are rarely used because of the risk of channeling, which can starve the bearing of lubricant. No. 0 or softer greases, at the other extreme, will accelerate softening and possibly promote leakage. If you’re contemplating a change in greases, Timken’s recommended properties are:

Soap Type: Lithium complex or equivalent

Dropping Point: 230C minimum

Consistency: NGLI No. 2 or No. 1

Additives: Corrosion and oxidation inhibitors, EP optional

Base Oil: Solvent refined petroleum

For conventional solid axle applications, of course, it’s much simpler: check and refill as necessary with the recommended differential lube. And remember that the ring gear will pick up lube and distribute it through the gearing, but a low oil level can have consequences at the wheel end. Bearings can be a good reason to change a leaking gasket.