Timken29520BImperial Tapered Roller Bearing Cup / Outer Race, 4.2500 in / 107.95 mm OD x 0.7500 in Wide, Class 3 Precision, Plain Single Cup – 1 Pc

Product Description

What this part is

This is an imperial tapered roller bearing cup — the outer race only. There are no rollers, no cage and no inner ring. The mating cone (inner ring with rollers) is a separate part number and is not included in this listing.

Decoding the designation

The published cup number is 29520, a plain unflanged single cup (Timken type TS). Its mating cones are 29585, 29580, 29582, 29586, 29588 and 29590; 29585 gives a 2.5000 in / 63.500 mm shaft bore. The trailing -3 (also written *3 or #3) is Timken’s precision Class 3: Timken tapered roller classes run Class 4 (standard commercial), then Class 3, Class 0 and Class 00 in increasing precision, so this cup is held to tighter bore and runout tolerances than the standard part. The B in 29520B is a supplier/house suffix rather than a Timken catalogue code; it is carried here so the number remains searchable.

Correcting the source data

Earlier copy on this listing gave the outside diameter as 4-3/4 in and called the part a flanged cup. The published 29520 cup is 4.2500 in / 107.95 mm outside diameter and is a plain, unflanged cup — there is no flanged variant in the 295xx series. The 0.7500 in width in the original copy is correct. Bore your housing for 4.2500 in.

Published dimensions and mounting data

Cup outside diameter (D): 4.2500 in / 107.95 mm
Cup width (C): 0.7500 in / 19.050 mm
Housing backing shoulder diameter (Da): 4.09 in / 103.89 mm
Housing backing shoulder diameter (Db): 3.78 in / 96.01 mm
Maximum housing fillet radius cleared: 0.130 in / 3.30 mm
e factor: 0.46 · Y factor: 1.31 · geometry factor Cg: 0.111
Weight: 1.9 lb / 0.8 kg

Load ratings are published against the cone, because a rating only exists for a cone-and-cup pair. None is quoted here, since an assembly rating on a cup-only listing would mislead.

What these specs mean in practice

The 295xx family is a shallow, wide-envelope taper used heavily in trailer and light-truck wheel ends and in gearbox output positions. The e value of 0.46 is comparatively high, which means the bearing tolerates a fair amount of thrust before the calculation switches to the thrust-governed formula — useful in wheel ends where cornering load arrives axially. Class 3 precision on a cup mainly buys you a rounder, more concentric seat, which is what keeps a preloaded pair from running hot on one side.

Quantity and configuration

This listing ships 1 Pc — one cup. No cone, no rollers, no seal, no spacer.

Fitting notes

Press the cup into the housing from its back face using a flat driver that spans the full ring rim; never strike the raceway lip. Seat it hard against the housing shoulder before attempting any setting — a cup left short of its shoulder reads as end play that no amount of nut adjustment will properly remove. Keep the housing fillet within 0.130 in so the corner clears.

Interchange guidance

29520 is a standardised imperial cup number, so 29520 cups from Timken, Bower/BCA, Koyo, NTN and Federal-Mogul share the same envelope and interchange. Choose the cone by shaft size from the 295xx list above. 29521 is a related size, not an equivalent — same family, different width — and the standard-precision 29520 shares this envelope but not the Class 3 tolerance grade.