Timken369-STapered Roller Bearing Cone Only 1-7/8″ Bore 0.8750″ Wide Class 3 Series 365, 17 Rollers

Product Description

What this part is

This is a single-row tapered roller bearing cone in the 365 series — the inner ring together with its tapered rollers and cage. It is not a complete bearing. Inch tapered roller bearings are two-piece: the cone (inner ring plus roller and cage set) and the cup (the separate outer race, pressed into the housing). This listing is the cone only, and no cup is included. That is the first thing to get straight, because a cone on its own cannot carry load. If the cup already in your housing is smooth and unmarked, a cone-only replacement is the right and cheapest repair. If the cup raceway shows spalling, a wear step at the large end, or brinelling from static shock loading, replace both members together.

Published cone dimensions

Bore (d): 1.8750 in / 47.625 mmCone width (B): 0.8750 in / 22.225 mmSeries: 365Cage: stamped steelRollers: 17 per rowCone backface clear radius (R): 0.090 in / 2.29 mmCone backing shoulder da: 2.09 in / 53.09 mmCone backing shoulder db: 2.24 in / 56.90 mmCone weight: 0.38 kg
The roller count of 17 is more useful than it looks. It tells you the load is being shared across a relatively fine set of rollers, which is what gives this size its good running smoothness, and it is also a quick field check — if you are trying to confirm a cone with an illegible marking, count the rollers and compare against the family before you assume you have a 369.

Which cups this cone runs against

Published matching cups for the 369 cone are the 362, 362A and 362B. The 363 cup is in the same 365 family and may pair, but we were not able to verify that pairing in manufacturer data, so treat it as possible and unconfirmed rather than a recommendation. The 362 and 362A are not the same envelope: the 362A gives an assembly width T of 0.8125 in with a cup width C of 0.6501 in, while the 362 gives T 0.7874 in (20 mm) with C 0.6250 in. Same bore, same 3.5 in class of outside diameter, different overall width — which means different endplay if you swap them without re-setting. Identify the cup in your housing before you order.

Assembly data with the 362A cup

Bore d: 1.8750 in — Cup O.D. D: 3.5000 inAssembly width T: 0.8125 in — Cup width C: 0.6501 inHousing fillet radius r: 1.27 mmDynamic radial rating C1: 102,000 NC90: 26,400 N — Ca90: 14,400 NStatic rating C0: 95,800 NLoad factors: e 0.32, Y 1.88, K 1.83Effective load center a: −4.3 mmSet weight: 0.56 kg

Assembly data with the 362 cup

Cup O.D. D: 3.5433 in / 90 mmAssembly width T: 0.7874 in / 20 mm — Cup width C: 0.6250 inHousing fillet radius r: 2.03 mmHousing shoulder diameters: Da 84.10 mm, Db 81.03 mmLoad ratings: same as the 362A pairing above (C1 102,000 N, C90 26,400 N, Ca90 14,400 N, C0 95,800 N)
Note that the ratings are identical between the two pairings while the geometry is not. The ratings come from the cone’s roller complement, which does not change; the cup only changes how the set mounts and how wide it sits. That is exactly why you can substitute cups on paper and still end up with an assembly that will not come to the specified endplay.

What the e, Y and K factors mean in practice:
K (1.83 here) is the radial-to-thrust capability ratio, and it is the number you use to convert thrust load into an equivalent radial load for bearing life calculation. e (0.32) is the axial-to-radial load ratio threshold above which the thrust component changes the internal load distribution, and Y (1.88) is the thrust factor applied once you are above that threshold. The negative effective load center a of −4.3 mm tells you the effective load line falls inside the bearing backface — which matters when you are calculating the load split between two taper bearings in a straddle or overhung arrangement. On a straight like-for-like replacement you can ignore all of this. On a re-rate, these are the working numbers.

Why Class 3 is tighter than Class 2

Inch tapered roller bearing precision classes follow ANSI/ABMA Standard 19.2, and the numbering does not read the way most people expect. From loosest to tightest the order is Class 4 → Class 2 → Class 3 → Class 0 → Class 00. Class 3 is therefore tighter than Class 2 and looser than Class 0. Buyers regularly assume a bigger number means a tighter tolerance and order the wrong grade. Class 4 is the general commercial grade; Class 3 and Class 0 are precision grades for applications where bore and O.D. tolerance and running accuracy control the setting — machine tool spindles, precision reducers, instrument and positioning drives. The actual numeric tolerance bands for each class live inside ANSI/ABMA Std 19.2 and Timken’s engineering manual rather than on open catalog pages, so we are not going to quote figures we cannot cite. The ranking above is the part that changes purchasing decisions.

Decoding the designation, and what “-S” does and does not mean:
369 is the cone basic number in the 365 series. On the “-S” suffix: Timken does not publish a definition. A distributor-maintained suffix decode table labels “S” as “Special Feature Bearing”, meaning a variant of the basic 369 cone. We report that as third-party information, not as a manufacturer publication, because we could not confirm it in Timken’s own documentation. What we can say with confidence is that 369, 369A and 369-S are three distinct cones, not three names for one part. Do not treat them as freely interchangeable. If your machine was built with a 369-S, verify the cup pairing and the physical assembly width before dropping in a plain 369 or a 369A, because a “special feature” variant is by definition dimensionally or metallurgically different from the base part in some respect the base number does not capture.

Fitting notes

The cone is an interference fit on the shaft. Press or drive it using a tool that contacts the cone backface only — never the rollers, never the cage. Respect the 0.090 in / 2.29 mm backface clear radius and the backing shoulder diameters (da 53.09 mm, db 56.90 mm); a shaft fillet larger than the clear radius will hold the cone off its shoulder and you will never reach the correct setting. Once the cup and cone are both in place the assembly must be brought to the endplay or preload the OEM specifies. Do not intermix cones, roller-and-cage sets or cups from different production lots inside a matched assembly — roller and cage geometry is controlled within a lot to produce a specific setting.

Interchange guidance

369 is an industry-standard inch taper cone number produced to the same envelope by multiple manufacturers. Useful search forms include 369, 369S, 369-S, 369 S, 369A, and the set designations 369/362A, 369/362 and 369/362B. Always confirm which cup you are pairing to, and confirm precision class if your application is class-sensitive.