40×68×15 mm bearings
25 models from 5 brands across 3 types share this ISO 15 envelope: 40 mm bore, 68 mm outside diameter, 15 mm width (1.575×2.677×0.591 in), 14 mm radial section.
25 models fit this space 5 brands 24 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) |
|---|---|---|---|---|---|---|---|
| 6008 | Deep Groove Ball | SKF | open | CN | 17.8 | 11 | 190 |
| 6008-2RS | Deep Groove Ball | SKF | 2RS | CN | 17.8 | 11 | 200 |
| 6008-2RS-FAG | Deep Groove Ball | FAG | 2RS | CN | 17.8 | 11.5 | 202 |
| 6008-2RS-NSK | Deep Groove Ball | NSK | 2RS | CN | 18.4 | 11.5 | 190 |
| 6008-2RS-NTN | Deep Groove Ball | NTN | 2RS | CN | 18.6 | 11.5 | 190 |
| 6008-FAG | Deep Groove Ball | FAG | open | CN | 17.8 | 11.5 | 192 |
| 6008-NSK | Deep Groove Ball | NSK | open | CN | 18.4 | 11.5 | 190 |
| 6008-NTN | Deep Groove Ball | NTN | open | CN | 18.6 | 11.5 | 190 |
| 6008-RSR | Deep Groove Ball | SKF | RSR | CN | 17.8 | 11 | 200 |
| 6008-RSR-NSK | Deep Groove Ball | NSK | RSR | CN | 18.4 | 11.5 | 190 |
| 6008-RSR-NTN | Deep Groove Ball | NTN | RSR | CN | 18.6 | 11.5 | 190 |
| 6008-ZZ | Deep Groove Ball | SKF | ZZ | CN | 17.8 | 11 | 200 |
| 6008-ZZ-FAG | Deep Groove Ball | FAG | ZZ | CN | 17.8 | 11.5 | 200 |
| 6008-ZZ-NSK | Deep Groove Ball | NSK | ZZ | CN | 18.4 | 11.5 | 190 |
| 6008-ZZ-NTN | Deep Groove Ball | NTN | ZZ | CN | 18.6 | 11.5 | 190 |
| 7008 | Angular Contact Ball | GENERIC-ISO | open | CN | — | — | 182 |
| 7008-NTN | Angular Contact Ball | NTN | open | CN | 20.8 | 14.6 | 222 |
| N1008 | Cylindrical Roller | NTN | open | CN | 30.5 | 29 | 217 |
| NJ1008 | Cylindrical Roller | NTN | open | CN | 30.5 | 29 | 217 |
| NU1008 | Cylindrical Roller | NTN | open | CN | 30.5 | 29 | 217 |
| NU1008-ML | Cylindrical Roller | SKF | open | CN | 25.1 | 26 | 230 |
| NUP1008 | Cylindrical Roller | NTN | open | CN | 30.5 | 29 | 217 |
| W6008 | Deep Groove Ball | SKF | open | CN | 14.6 | 11.4 | 172 |
| W6008-2RS | Deep Groove Ball | SKF | 2RS | CN | 14.6 | 11.4 | 182 |
| W6008-ZZ | Deep Groove Ball | SKF | ZZ | CN | 14.6 | 11.4 | 183 |
Substitution verification checklist
- Load rating. Check C (dynamic) and C0 (static) against the original life calculation — the table above shows which models carry verified catalogue values.
- 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.
- 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.
- Cage and precision. Stamped steel, machined brass and polymer cages, and P0/P6/P5 tolerance classes, carry different speed and shock limits.
- 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: 6008, 6008-2RS, 6008-2RS-FAG, 6008-2RS-NSK, 6008-2RS-NTN, 6008-FAG, 6008-NSK, 6008-NTN, 6008-RSR, 6008-RSR-NSK, 6008-RSR-NTN, 6008-ZZ, 6008-ZZ-FAG, 6008-ZZ-NSK, 6008-ZZ-NTN, 7008, 7008-NTN, N1008, NJ1008, NU1008, NU1008-ML, NUP1008, W6008, W6008-2RS, W6008-ZZ.
Frequently asked questions
Are all 40×68×15 mm bearings interchangeable?
They share the same ISO 15 boundary dimensions — 40 mm bore, 68 mm OD, 15 mm width (1.575×2.677×0.591 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 25 models listed here and must be checked against the duty before substitution.
Is it a drop-in replacement if two bearings both measure 40×68×15?
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 40×68×15 mm in inches?
40×68×15 mm converts to 1.575×2.677×0.591 in, with a 14 mm (0.551 in) radial section height. These are the ISO 15 general-plan envelope dimensions shared across manufacturers, which is why models such as 6008, 6008-2RS, 6008-2RS-FAG mount in the same space despite different internal designs.