MPNbase

40×90×23 mm bearings

52 models from 4 brands across 6 types share this ISO 15 envelope: 40 mm bore, 90 mm outside diameter, 23 mm width (1.575×3.543×0.906 in), 25 mm radial section.

52 models fit this space 4 brands 52 with catalogue C rating

Dimensional interchange — verify before substituting

These bearings are interchangeable on boundary dimensions per ISO 15 — same bore, OD and width. They are not guaranteed drop-in equivalents: compare load ratings, seals, clearance, cage, precision and axial-locating design for the specific duty. Models without a catalogue C rating on this site carry ISO 15 geometry only; request the manufacturer table before a load-critical replacement.

Model Type Brand Seal Clearance C (kN) C0 (kN) Mass (g)
1308 Self-Aligning Ball NTN open — 29.8 9.7 727
1308-EKTN9 Self-Aligning Ball SKF open CN 33.8 11.2 680
1308-ETN9 Self-Aligning Ball SKF open CN 33.8 11.2 680
1308K Self-Aligning Ball NTN open — 29.8 9.7 727
1726308-2RS1 Insert (Y-bearings) SKF 2RS CN 41 24 610
21308C Spherical Roller NTN open CN 98 90 705
21308CK Spherical Roller NTN open CN 98 90 694
308 Deep Groove Ball SKF open CN 45.7 36 640
308-ZZ Deep Groove Ball SKF ZZ CN 45.7 36 640
6308 Deep Groove Ball SKF open CN 42.3 24 630
6308-2RS Deep Groove Ball SKF 2RS CN 42.3 24 640
6308-2RS-FAG Deep Groove Ball FAG 2RS CN 47 25 654
6308-2RS-NSK Deep Groove Ball NSK 2RS CN 45 24 636
6308-2RS-NTN Deep Groove Ball NTN 2RS CN 45 24 630
6308-FAG Deep Groove Ball FAG open CN 47 25 596
6308-NSK Deep Groove Ball NSK open CN 45 24 636
6308-NTN Deep Groove Ball NTN open CN 45 24 630
6308-RSR Deep Groove Ball SKF RSR CN 42.3 24 650
6308-RSR-NSK Deep Groove Ball NSK RSR CN 45 24 636
6308-RSR-NTN Deep Groove Ball NTN RSR CN 45 24 630
6308-ZZ Deep Groove Ball SKF ZZ CN 42.3 24 650
6308-ZZ-FAG Deep Groove Ball FAG ZZ CN 47 25 665
6308-ZZ-NSK Deep Groove Ball NSK ZZ CN 45 24 636
6308-ZZ-NTN Deep Groove Ball NTN ZZ CN 45 24 630
7308 Angular Contact Ball SKF open CN 46.2 30.5 620
7308-ACCBM Angular Contact Ball SKF open CN 56 36 680
7308-BE-2RZP Angular Contact Ball SKF RSR CN 46.2 30.5 620
7308-BECBM Angular Contact Ball SKF open CN 50 32.5 680
7308-BECBP Angular Contact Ball SKF open CN 50 32.5 620
7308-BECBY Angular Contact Ball SKF open CN 53 35.5 640
7308-BEGAPH Angular Contact Ball SKF open CN 50 32.5 620
7308-BEP Angular Contact Ball SKF open CN 46.2 30.5 620
7308-NTN Angular Contact Ball NTN open CN 54 33 625
7308B Angular Contact Ball NTN open CN 49.5 30.5 636
N308 Cylindrical Roller NTN open CN 65 57 643
N308-ECP Cylindrical Roller SKF open CN 93 78 650
N308EA Cylindrical Roller NTN open CN 98.5 81.5 658
NF308 Cylindrical Roller NTN open CN 65 57 643
NF308EA Cylindrical Roller NTN open CN 98.5 81.5 658
NJ308 Cylindrical Roller NTN open CN 65 57 643
NJ308-ECP Cylindrical Roller SKF open CN 93 78 670
NJ308EA Cylindrical Roller NTN open CN 98.5 81.5 658
NU308 Cylindrical Roller SKF open CN 93 78 650
NU308-NTN Cylindrical Roller NTN open CN 65 57 643
NU308EA Cylindrical Roller NTN open CN 98.5 81.5 658
NUP308 Cylindrical Roller NTN open CN 65 57 643
NUP308-ECP Cylindrical Roller SKF open CN 93 78 680
NUP308EA Cylindrical Roller NTN open CN 98.5 81.5 658
QJ-308-MA Angular Contact Ball SKF open CN 78 64 780
QJ-308-N2MA Angular Contact Ball SKF open CN 78 64 780
QJ-308-N2PHAS Angular Contact Ball SKF open CN 78 64 780
QJ308 Angular Contact Ball NTN open CN 67 91.5 780

Note: catalogue dynamic load ratings for this envelope span 29.8– 98.5 kN — a 231% spread between designs in the very same 40×90×23 mm space. The higher-rated unit is not an upgrade for every duty (it may run at lower limiting speed), but ignoring the gap will over- or under-life the replacement.

Substitution verification checklist

  1. Load rating. Check C (dynamic) and C0 (static) against the original life calculation — the table above shows which models carry verified catalogue values.
  2. Sealing. Open, -ZZ shields and -2RS contact seals are not equivalent in friction, speed or contamination protection; match the housing environment, not just the suffix on the old box.
  3. Internal clearance. CN/C3/C4 changes with fit and operating temperature; an interference inner-ring mount commonly needs C3 where the bench bearing ran CN.
  4. Cage and precision. Stamped steel, machined brass and polymer cages, and P0/P6/P5 tolerance classes, carry different speed and shock limits.
  5. Locating behaviour. Within one envelope an NU cylindrical roller floats axially while an NJ/NUP locates; ball designs take thrust that roller locating schemes do not. Preserve the shaft's locating arrangement.

Browse all 40 mm bore bearings for wider or narrower sections, or open a model page for naming-rule decode, applications and graded cross references: 1308, 1308-EKTN9, 1308-ETN9, 1308K, 1726308-2RS1, 21308C, 21308CK, 308, 308-ZZ, 6308, 6308-2RS, 6308-2RS-FAG, 6308-2RS-NSK, 6308-2RS-NTN, 6308-FAG, 6308-NSK, 6308-NTN, 6308-RSR, 6308-RSR-NSK, 6308-RSR-NTN, 6308-ZZ, 6308-ZZ-FAG, 6308-ZZ-NSK, 6308-ZZ-NTN, 7308, 7308-ACCBM, 7308-BE-2RZP, 7308-BECBM, 7308-BECBP, 7308-BECBY, 7308-BEGAPH, 7308-BEP, 7308-NTN, 7308B, N308, N308-ECP, N308EA, NF308, NF308EA, NJ308, NJ308-ECP, NJ308EA, NU308, NU308-NTN, NU308EA, NUP308, NUP308-ECP, NUP308EA, QJ-308-MA, QJ-308-N2MA, QJ-308-N2PHAS, QJ308.

Frequently asked questions

Are all 40×90×23 mm bearings interchangeable?

They share the same ISO 15 boundary dimensions — 40 mm bore, 90 mm OD, 23 mm width (1.575×3.543×0.906 in) — so they fit the same shaft, housing bore and axial space. Interchangeability ends at the envelope: dynamic load rating, seal arrangement, internal clearance, cage and precision class differ between the 52 models listed here and must be checked against the duty before substitution.

Is it a drop-in replacement if two bearings both measure 40×90×23?

Only after verification. Confirm five things in order: (1) the C/C0 load ratings meet the original life calculation, (2) the seal type is equivalent or acceptable for the contamination level (open vs -ZZ vs -2RS), (3) internal clearance matches (CN/C3/C4 — an interference fit changes residual play), (4) cage material and precision class suit the speed, and (5) the axial-locating behaviour is the same (for example an NU cylindrical roller floats while an NJ locates one way). Same dimensions alone never guarantee equal performance.

What is 40×90×23 mm in inches?

40×90×23 mm converts to 1.575×3.543×0.906 in, with a 25 mm (0.984 in) radial section height. These are the ISO 15 general-plan envelope dimensions shared across manufacturers, which is why models such as 1308, 1308-EKTN9, 1308-ETN9 mount in the same space despite different internal designs.