17580-17520 bearing: complete specifications & equivalents
The 17580-17520 is a ANSI ABMA 19.2 radial bearing sized 15.875 x 42.862 x 16.67 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 15.875 mm |
| Outer diameter D | 42.862 mm |
| Width B | 16.67 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 29.6 kN |
| Basic static load rating C0 | 26 kN |
| Limiting speed (mechanical) | 9800 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 123 g |
| Manufacturer designation | NTN 4T-17580/17520 |
| Standard | ANSI ABMA 19.2 |
| Catalog version | NTN 2203E 2026-09-25 |
| Last verified | 2026-10-01 |
Source: catalog reference (NTN 2203E 2026-09-25) · extracted 2026-10-01
Parameters extracted from the official NTN Ball and Roller Bearings catalogue (NTN 2203E 2026-09-25); 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 & 4t-inch-series range
| Bore d | 0.625 in |
|---|---|
| Outer diameter D | 1.687 in |
| Width B | 0.656 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 13.5 mm |
| Smallest bore in 4t-inch-series | 12.7 mm |
| Largest outer diameter in 4t-inch-series | 260 mm |
| Width range across 4t-inch-series | 10.998–77.788 mm |
| Bore position in 4t-inch-series (smallest first) | 3 of 148 |
| Bore above smallest 4t-inch-series size | 3.1750000000000007 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 17580 | 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 17580-17520 model number is decoded
For an inch shaft of 15.875 mm carrying combined radial and thrust load, NTN lists 4T-17580/17520, a single-row 4T tapered roller set of 29.6 kN C and 26 kN C0 inside the 42.862 mm OD cup. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 17580 identifies the cone of 15.875 mm (0.625 in) bore by catalogue lookup, and 17520 fixes the 42.862 mm OD. The 13.5 mm radial section over the 15.875 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. The printed 29.6/26 kN ratings belong to the assembled 17580+17520 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Back-to-back (O) and face-to-face (X) arrangements of two 4T-17580/17520 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.
Typical equipment & failure modes
Common applications
- lawn, garden and powersport axle positions
- small inch-shaft gearbox and reducer shafts
- conveyor roller and pulley shafts in inch-frame machinery
- utility-vehicle differential and pinion supports
Known failure patterns
- cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film
- false brinelling on a stationary pair exposed to vibration during transport or standby
- preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play
- cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling
- indentation of the raceways by hard particles in an open, unsealed arrangement
Selection pitfalls — read before you substitute
- At 15.875 mm (0.625 in) bore the thin cone and cup distort under an over-tight shaft nut; set the 4T-17580/17520 pair with a dial indicator on end play rather than by locknut feel.
- The pure-numeric inch family at 15.875 mm bore (42.862×16.67 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 17580/17520 reference at purchase.
- An unloaded 4T-17580/17520 near 9,800 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.
- Replacing one half of an adjusted pair without resetting end play negates the 16.67 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.
- Replacing one half of an adjusted pair without resetting end play negates the 16.67 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.
- The 29.6/26 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-17580/17520; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive.
Frequently asked questions
What are the dimensions and catalogue ratings of NTN 4T-17580/17520?
4T-17580/17520 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 15.875 mm bore (0.625 in), 42.862 mm outside diameter and 16.67 mm assembled width T (1.687 × 0.656 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 29.6 kN, C0 26 kN, grease limiting speed 9,800 r/min, oil speed 13,000 r/min, mass about 123 g. It is an open, separable cone/cup set with a pressed-steel cage.
Are the cone and cup of 4T-17580/17520 interchangeable separately?
Yes — ABMA inch parts are individually interchangeable: the 17580 cone or the 17520 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 29.6/26 kN ratings change with the cup.
What is the difference between 4T-17580/17520 and a metric ISO 355 tapered bearing?
4T-17580/17520 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 15.875×42.862×16.67 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting.
What does the 4T prefix on 4T-17580/17520 mean?
4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare 17580/17520 references; the 4T spelling is retained among this page's search aliases.
Why does 4T-17580/17520 list two speeds, 9,800 and 13,000 r/min?
The lower figure, 9,800 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-17580/17520 at 13,000 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling.
Reviewed & verified by the MPN Base engineering desk against source catalog NTN 2203E 2026-09-25 on 2026-10-01. Read our editorial & correction policy.