32307 bearing: complete specifications & equivalents
The 32307 is a ISO 355 radial bearing sized 35 x 80 x 32.75 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Bore diameter d | 35 mm |
| Outer diameter D | 80 mm |
| Width B | 32.75 mm |
| Seal / shield | open |
| Internal clearance | CN available |
| Tolerance class | P0 |
| Cage | steel, stamped ribbon (J-type) |
| Operating temperature | -30 to +120 °C |
| Mass (geometry estimate) | 679 g |
| Standard | ISO 355 |
| Catalog version | iso355-geometry |
| Last verified | 2026-09-24 |
Source: ISO 15 boundary-dimensions standard · extracted 2026-09-24
Standard-interchange bearing: dimensions per ISO 15; CN clearance, P0 tolerance and a stamped-steel cage are catalogue defaults unless the supplier states otherwise, and mass is a geometry-derived estimate. Brand catalogue load ratings and limiting speeds for 32307 are being backfilled — use the inquiry form for certified values.
Dimensions in inches & 32300-series range
| Bore d | 1.378 in |
|---|---|
| Outer diameter D | 3.15 in |
| Width B | 1.289 in |
| ISO bore code | 07 |
| Radial section height (D−d)/2 | 22.5 mm |
| Smallest bore in 32300-series | 20 mm |
| Largest outer diameter in 32300-series | 240 mm |
| Width range across 32300-series | 22.25–84.5 mm |
| Bore position in 32300-series (smallest first) | 4 of 19 |
| Bore above smallest 32300-series size | 15 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 32307 | ISO 15 | full Dimensions and internal design equivalent — standard interchange. | ISO 15 boundary-dimension envelope; brand-specific OEM equivalents (NSK/FAG/NTN) pending multi-source data. |
Interchange levels: full standard interchange · partial verify parameters · verify manual confirmation required. Links resolve to the equivalent model's specification page where available.
How the 32307 model number is decoded
In the 32300-series the last two digits of 32307 encode the bore: code 07 = 35 mm (code × 5 from 04 upward). The ISO 355 envelope is 80 mm outside diameter and 32.75 mm total assembly width T over the separable cone and cup — 1.378 × 3.15 × 1.289 in, with a 22.5 mm radial section height. Tapered rollers carry combined radial and single-direction axial load; bidirectional thrust needs an opposed pair (X face-to-face or O back-to-back) adjusted at fit-up. With a rotating cone on a 35 mm shaft, typical catalogue practice is a k5 shaft seat with an H7 housing bore, EP lubrication and a defined end-play setting — verify against the load direction and magnitude.
Typical equipment & failure modes
Common applications
- small trailer axles
- light differential pinions
- steering knuckles
- small gearbox shafts
- agricultural implement wheels
Known failure patterns
- roller large-end smearing and scoring against the inner-ring guide rib from loss of the EP lubricant film
- raceway spalling at the roller-rib junction after the L10 life or sustained axial overload
- over-preload heat: a shim stack cut too thin drives contact stress up and seizes the cone on the seat
- under-preload end play that lets the rollers skid, producing noise and false brinelling
- water and grit pitting in unsealed hubs where the cup-cone joint acts as a debris entry path
Selection pitfalls — read before you substitute
- At 35 mm bore the small 32307 is commonly factory-adjusted in a hub unit; an after-market fit-up must reproduce the specified end play (a typical starting range of 0.02–0.10 mm at the 35 mm shaft) or the wheel runs hot within the first hundred kilometres.
- The 323 heavy wide series at 35 mm bore (80×32.75 mm) is a steep-angle, high-thrust row for heavy final drives; its 22.5 mm section and 32.75 mm width dwarf the 30207, and its speed ceiling is the lowest of the four series.
- Before fitting 32307, machine the 35 mm shaft seat and 80 mm housing bore with a relief or small fillet so nothing bridges the bearing chamfer; the 32.75 mm-wide cone and cup only load correctly when the full faces abut, and a large radius pinches the 22.5 mm radial section.
- The 32307 cup drives into the 80 mm housing bore with a sleeve against its outer face only; pressure on the inner ring or cage transfers through the rollers and leaves indentations that become spalls within the 32.75 mm load zone.
- Inspect the removed 32307 cone and cup as a pair: pitting on the 80 mm cup with a clean cone usually means seal failure and water ingress, while rib scoring on the 35 mm cone points to wrong preload or lost EP film — the two faults need different corrections.
- Set running clearance (or preload) with the shim pack or adjusting nut at fit-up; a 35 mm-bore 32307 that is too tight overheats and scores the rib, one too loose develops end play and noise — follow the torque-and-untighten procedure.
- The sliding contact between roller large ends and the inner-ring rib needs extreme-pressure lubricant; use an EP gear oil or EP grease (GL-5 class in axles) rather than plain bearing grease or the rib will smear in the first heavy run.
Frequently asked questions
What are the dimensions of a 32307 tapered roller bearing?
A 32307 single-row metric tapered roller bearing per ISO 355 has a 35 mm bore, 80 mm outer diameter and 32.75 mm total assembly width (1.378 × 3.15 × 1.289 in), a 22.5 mm radial section and roughly 679 g geometry-based estimated mass; catalogue masses vary with roller and cage design.
How does the 32307 bore code work?
The last two digits of 32307 are bore code 07, giving 07 × 5 = 35 mm bore — the same convention as 6xx ball bearings, starting at code 04 (20 mm). The 80 mm OD and 32.75 mm width come from the ISO 355 diameter and width series, not the bore code alone.
What is the cone and cup of 32307?
Tapered roller bearings are separable: the cone is the inner ring with the tapered rollers and cage, the cup is the outer ring. 32307 denotes a matched cone-and-cup set. They are fitted separately — cone pressed on the shaft, cup in the housing — and adjusted against each other.
How is the preload or clearance of 32307 set?
At fit-up the 35 mm-bore cone is tightened against the cup while the hub is rotated, seated, then backed off to the specified end play — a typical starting range of 0.02–0.10 mm for a 35 mm bore — and locked with shims, a locknut or a spacer. Too tight overheats and seizes the rib; too loose causes skid, noise and early wear. Confirm the exact figure in the hub or axle-maker procedure.
Can 32307 take axial load in both directions?
A single 32307 takes thrust in one direction only — the roller large ends bear against the inner-ring rib under load. Bidirectional axial load requires an opposed pair: X (face-to-face) tolerates misalignment slightly better, O (back-to-back) gives a wider load centre and more moment stiffness.
Reviewed & verified by the MPN Base engineering desk against source catalog iso355-geometry on 2026-09-24. Read our editorial & correction policy.