Timken497-90204TDO Two-Row Tapered Roller Bearing Assembly – 3.3750 in Bore, 5.3750 in Outer Diameter, 2.7500 in Width, Class 3, Case-Hardened Steel

Product Description

What this part is

A Timken 497-90204 complete two-row tapered roller bearing assembly in the TDO configuration, meaning tapered double outer. It is supplied as four pieces: two 497 cones, one 493-D double cup that both cones run in, and one X3S-497 cone spacer. Bore 3.3750 in, outside diameter 5.3750 in, overall assembly width 2.7500 in. Case-hardened steel throughout with stamped steel cages.

Decoding the designation

The 497 is the cone, meaning the inner ring complete with its rollers and cage. The 493D is the cup, the outer race, and the D marks it as a double cup: one outer ring with two raceways ground into it, which is why it accepts two cones. The X3S-497 is a cone spacer, the ground ring that sits between the two cone backfaces and fixes the row spacing. The -90204 suffix identifies the whole thing as a factory-matched assembly rather than a set of loose components. The asterisk-3 and hash-3 marks stamped alongside each component designation are Timken’s precision Class 3 markings.

What these specs mean in practice

Class 3 is a tightened precision grade above Timken’s standard tolerance, controlling bore, outside diameter and running accuracy more closely, and it is broadly the ABEC 5 equivalent. That buys lower runout and smoother running, which is why Class 3 inch tapers turn up in industrial gearboxes, pump shafts and machine spindles rather than general vehicle service. The TDO layout puts both rows inside a single outer ring, so the bearing seats in one straight housing bore, carries thrust in both directions, and resists overturning moments because the two rows are spaced apart.

Quantity and configuration

One complete assembly, supplied as four pieces: two 497 cones, one 493-D double cup and one X3S-497 cone spacer.

Fitting notes

The double cup seats in a straight housing bore and the two cones press onto the shaft with the X3S-497 spacer between their backfaces. Row spacing and internal setting are established by the spacer and the matched assembly number, so the four pieces are ground as a unit.

Interchange guidance

The 497 cone also runs against the 493 single cup, which is the same raceway in a single-row form. A 497/493 pair covers one row of this assembly and is a related configuration rather than an interchange, since it carries neither the second row, the spacer, nor the matched internal setting. Class 3 and standard-tolerance versions of the same numbers are separate grades.