BEARINGDEXDeep groove ball
6308 bearing
40 mm bore, 90 mm outside diameter, 23 mm width (1.5748 × 3.5433 × 0.9055 in).
Dimensions
| mm | inch | |
|---|---|---|
| Bore d | 40 | 1.5748 |
| Outside diameter D | 90 | 3.5433 |
| Width B | 23 | 0.9055 |
Quick numbers
| Pitch diameter dm | 65.0 mm |
| Section height (D − d)/2 | 25.0 mm |
| n·dm at 1,800 rpm | 117,000 |
| n·dm at 3,600 rpm | 234,000 |
Compare against the maker's limiting speed. Speed calculator · L10 life
What the number means
6Deep groove ball
3Diameter series 3: medium. Width series 0 is implied and left off.
08Bore code 08 × 5 = 40 mm
How each brand writes it
Same bearing, every maker's notation| Version | SKF | FAG | NSK | NTN | Koyo | NACHI |
|---|---|---|---|---|---|---|
| Open | 6308 | 6308 | 6308 | 6308 | 6308 | 6308 |
| Shields both sides | 6308-2Z | 6308-2ZR | 6308ZZ | 6308ZZ | 6308ZZ | 6308ZZE |
| Contact seals both sides | 6308-2RSH | 6308-2RSR | 6308DDU | 6308LLU | 6308-2RS | 6308-2NSE |
| Contact seals both sides, C3 | 6308-2RSH/C3 | 6308-2RSR-C3 | 6308DDUC3 | 6308LLUC3 | 6308-2RSC3 | 6308-2NSE C3 Verify |
| Non-contact seals both sides | 6308-2RSL | 6308-2BRS Verify | 6308VV | 6308LLB | 6308-2RU Verify | 6308-2NKE Verify |
| Shields both sides, C3 | 6308-2Z/C3 | 6308-2ZR-C3 | 6308ZZC3 | 6308ZZC3 | 6308ZZC3 | 6308ZZE C3 Verify |
Same size, different bearing
These share the 40 × 90 × 23 mm envelope but carry load differently. They aren't drop-in swaps.