32307C bearing: complete specifications & equivalents
The 32307C 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 |
|---|---|
| Brand | NTN |
| Bore diameter d | 35 mm |
| Outer diameter D | 80 mm |
| Width B | 32.75 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 103 kN |
| Basic static load rating C0 | 117 kN |
| Limiting speed (mechanical) | 4800 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 804 g |
| Manufacturer designation | NTN 32307C |
| Standard | ISO 355 |
| Catalog version | NTN Ball and Roller Bearings CAT.No.2203E |
| Last verified | 2026-10-01 |
Source: catalog reference (NTN Ball and Roller Bearings CAT.No.2203E) · extracted 2026-10-01
Parameters extracted from the official NTN Ball and Roller Bearings catalogue (NTN Ball and Roller Bearings CAT.No.2203E); NTN® is a trademark of NTN Corporation, used here for identification only — mpnbase is not an authorized NTN distributor. Boundary dimensions are ISO 15 interchangeable; current production values may differ, verify at ntnglobal.com.
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 | — |
| Radial section height (D−d)/2 | 22.5 mm |
| Smallest bore in 32300-series | 20 mm |
| Largest outer diameter in 32300-series | 460 mm |
| Width range across 32300-series | 22.25–154 mm |
| Bore position in 32300-series (smallest first) | 5 of 30 |
| Bore above smallest 32300-series size | 15 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 32307C | 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 32307C model number is decoded
For a 35 mm shaft with a thrust component, NTN lists 32307C, a metric 4T tapered roller bearing of 103 kN C and 117 kN C0 inside the 80 mm OD, 32.75 mm-wide assembled set. Reading the designation: the leading five digits follow the ISO 355 metric plan (dimension family plus two-digit bore code), and 32307C resolves to 35 mm bore; the NTN factory mark 4T is stamped on cone and cup but is a brand mark, not a size code, so the catalogue sku is printed without it. Suffix reading on 32307C: the trailing A/C/D (or E1) letter marks an NTN contact-angle or internal-design revision of the base number, not a seal or clearance code; the suffix is part of the order number and the variants are not interchangeable articles. Imperial cross-check for the drawing: 35×80×32.75 mm is 1.378 × 3.15 × 1.289 in; ISO 355 makes the envelope interchangeable but C/C0, 103/117 kN, is NTN-specific. After mounting check the contact pattern with marking blue: a pattern biased to the large or small roller end means the 35 mm pair is misadjusted and the 32.75 mm T set will edge-load in service.
Typical equipment & failure modes
Common applications
- bevel and helical pinion drives with high thrust component
- pump and compressor drive shafts carrying combined load
- machine-tool gearbox and headstock shafts
- axle final-drive and differential positions
Known failure patterns
- cup creep and housing fretting when the specified outer-ring press fit is not achieved
- preload loss from racewear when one bearing of the paired set is replaced without re-adjusting end play
- rib scoring when axial load is carried beyond the cone rib capacity of the adjusted pair
- cage fatigue when the pair is run continuously near the grease limiting speed without oil cooling
- water-induced pitting when the open bearing is exposed to washdown without external seals
Selection pitfalls — read before you substitute
- Hub and pinion bearings of this 35 mm bore class are commonly adjusted in pairs; verify end play against the axle drawing and re-torque after bedding-in rather than trusting the initial preload on 32307C.
- The extra-heavy 32300 family at 35 mm bore (80×32.75 mm assembled) carries more capacity than the lighter 320/329 sections but generates more preload heat; confirm oil availability before running near the 6,400 r/min oil ceiling.
- Grease packs must leave free volume in the 32.75 mm-wide set; over-greasing a paired bearing churning at the 6,400 r/min oil-band speed raises temperature and destroys the preload setting.
- The 22.5 mm section leaves little room for an oversized shaft fillet; check the mounting-chamfer table for 32307C or the ring will bottom out on the radius instead of the shoulder face.
- ISO 355 makes the 35×80 mm envelope interchangeable but not the ratings: NTN prints 103/117 kN for this execution, and a cheaper same-number part can differ in roller complement and steel.
- The 103/117 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 32307C (ISO 355 5FE); internal geometry legitimately differs between manufacturers, so re-verify ratings, adjustment and suffix before substituting another make on a rated drive.
Frequently asked questions
What are the dimensions and catalogue ratings of NTN 32307C?
32307C is a metric 4T tapered roller bearing to ISO 355: 35 mm bore, 80 mm outside diameter and 32.75 mm assembled width T (1.378 × 3.15 × 1.289 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 103 kN, C0 117 kN (2203E prints no Pu for this size), grease limiting speed 4,800 r/min, oil speed 6,400 r/min, mass about 804 g. It is an open, separable cone/cup bearing with a pressed-steel cage.
What does the 4T prefix mean on 32307C?
4T is NTN's tapered roller bearing brand mark, stamped on the cone and cup in the factory. It identifies the NTN 4T programme and is not a dimension, so the catalogue and this page list the bare ISO 355 number (32307C); the lower-case 4t- factory spelling of the code is retained among the search aliases.
How does the 32307C designation encode the 35 mm bore and what is 5FE?
last two digits 07 are the ISO bore code, ×5 = 35 mm (codes 00–03 use the 10/12/15/17 exception table). The 80 mm OD and 32.75 mm assembled T follow the ISO 355 dimension-series plan. 5FE is the maker-neutral ISO 355 abbreviation for this dimension series (the same code other manufacturers print); 4T is NTN's own brand mark.
Why does 32307C list two speeds, 4,800 and 6,400 r/min?
The lower figure, 4,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 32307C at 6,400 r/min because oil removes rib-contact heat better. Real limits still depend on preload, oil flow and cooling.
What does the suffix on 32307C mean?
Suffix reading on 32307C: the trailing A/C/D (or E1) letter marks an NTN contact-angle or internal-design revision of the base number, not a seal or clearance code; the suffix is part of the order number and the variants are not interchangeable articles.
Reviewed & verified by the MPN Base engineering desk against source catalog NTN Ball and Roller Bearings CAT.No.2203E on 2026-10-01. Read our editorial & correction policy.