Timken377WImperial Tapered Roller Bearing Cone, 2.0625 in / 52.388 mm Bore, Mates Cup 372A – 1 Pc

Product Description

What this part is

This is an imperial single-row tapered roller bearing cone — the inner ring with its tapered rollers and cage. It is one half of a tapered roller bearing. The mating cup (outer race) is a separate part number and is not included in this listing.

Decoding the designation

The base number is 377, a standard imperial cone; its matching cup is 372A (372 is also listed), so a complete single-row bearing is a 377 cone plus a 372A cup. The W in 377W is a legacy variant suffix carried on the ring or carton; Timken publishes no decode for it, so it is treated here as an alternate form of the number rather than a claimed specification. The dimensions and ratings below are the published 377 values, which are what govern fit.

Published dimensions

Cone bore (d): 2.0625 in / 52.388 mm
Inner ring width (B): 0.8750 in / 22.225 mm
Mating cup 372A outside diameter (D): 3.8125 in / 96.838 mm
Mating cup 372A width (C): 0.7500 in / 19.050 mm
Cone weight: 3.56 lb / 1.614 kg

Published ratings and mounting data

The ratings below are catalogue values for the complete 377/372A single-row assembly, not for the cone alone.

Dynamic radial rating C1 (1 million rev basis): 23,400 lbf / 104,000 N
Dynamic radial rating C90 (90 million rev basis): 6,070 lbf / 27,000 N
Dynamic axial rating Ca90: 3,520 lbf / 15,700 N
Static radial rating C0: 22,700 lbf / 101,000 N
K factor: 1.73 · e: 0.34 · Y: 1.77 · geometry factor Cg: 0.0816
Effective load centre: −0.15 in / −3.8 mm (inside the cone backface)
Maximum shaft fillet radius cleared: 0.09 in / 2.300 mm
Shaft backing shoulder diameter, frontface (da): 2.28 in / 58 mm
Shaft backing shoulder diameter, backface (db): 2.44 in / 62 mm
Cup 372A housing backing shoulder: Da 3.56 in / 90.42 mm, Db 3.39 in / 86.11 mm; max housing fillet 0.06 in / 1.52 mm

What these specs mean in practice

A K factor of 1.73 is the general-purpose middle of the tapered roller range: enough thrust capacity to handle helical gear reaction or a cornering load, enough radial capacity to be the main support, and predictable induced thrust for the opposing bearing. The narrow 0.7500 in cup keeps the axial envelope short for a 2.0625 in shaft, which is why the 372/377 pairing is a common choice in gear reducers and shaft-mounted drives where housing length is constrained.

Quantity and configuration

This listing ships 1 Pc — one 377 cone. No cup, no spacer, no seal.

Fitting notes

Press the cone on square, loading the backface only and never the rollers or cage. Keep the shaft shoulder within the da/db range. Note the mismatch worth planning for: the cone tolerates a 0.09 in shaft fillet but the mating 372A cup only a 0.06 in housing fillet, so the housing corner must be the sharper of the two. Set the end play or preload after the cup is fully seated.

Interchange guidance

377 is a dimensionally standardised imperial cone, so 377 cones from Timken, Koyo, NTN, Bower/BCA, SKF and Federal-Mogul interchange with one another and with any maker’s 372A cup. 377A is a related size, not an equivalent, and 372 versus 372A differ in cup detail — order the cup by number against your housing. A 377W ring marking should be read as a 377 for fitting purposes.