6003-FAG bearing: complete specifications & equivalents

The 6003-FAG is a ISO 15 radial bearing sized 17 x 35 x 10 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.

Bearing dimension schematic Front view shows outer diameter D and bore d; side section shows width B. D = 35 mm d = 17 B = 10 mm side section front view
Principal dimensions: bore d 17 mm, outer diameter D 35 mm, width B 10 mm. Schematic, not to scale.

Specification table

ParameterValue
Brand FAG
Bore diameter d 17 mm
Outer diameter D 35 mm
Width B 10 mm
Material GCr15
Seal / shield open
Internal clearance CN
Tolerance class P0
Cage steel
Basic dynamic load rating C 6.4 kN
Basic static load rating C0 3.25 kN
Reference speed (thermal) 20300 rpm
Limiting speed (mechanical) 31000 rpm
Mass 38 g
Manufacturer designation FAG 6003
Standard ISO 15
Catalog version HR 1 Rolling Bearings (Jan 2020)
Last verified 2026-09-25

Source: catalog reference (HR 1 Rolling Bearings (Jan 2020)) · extracted 2026-09-25

Parameters extracted from the official FAG Rolling Bearings catalogue (HR 1 Rolling Bearings (Jan 2020)); FAG® is a trademark of Schaeffler Technologies AG & Co. KG, used here for identification only — mpnbase is not an authorized FAG/Schaeffler distributor. Boundary dimensions are ISO 15 interchangeable; current production values may differ, verify at schaeffler.com.

Dimensions in inches & 6000-series range

Bore d0.669 in
Outer diameter D1.378 in
Width B0.394 in
ISO bore code03
Radial section height (D−d)/29 mm
Smallest bore in 6000-series4 mm
Largest outer diameter in 6000-series1150 mm
Width range across 6000-series4–155 mm
Bore position in 6000-series (smallest first)10 of 61
Bore above smallest 6000-series size13 mm

Cross references & equivalents

Equivalent modelBrandMatch levelNote
6003-2RS-NSK NSK partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 17×35×10 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6003-RSR-NSK NSK partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 17×35×10 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6003-ZZ-NSK NSK partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 17×35×10 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6003-NSK NSK full
Dimensions and internal design equivalent — standard interchange.
Same 17×35×10 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6003 SKF full
Dimensions and internal design equivalent — standard interchange.
Same 17×35×10 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6003-2RS SKF partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 17×35×10 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6003-RSR SKF partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 17×35×10 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
6003-ZZ SKF partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 17×35×10 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
W6003-2RS SKF partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 17×35×10 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
W6003-ZZ SKF partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 17×35×10 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.
W6003 SKF partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same 17×35×10 mm envelope per ISO 15; seal variant and load ratings may differ — confirm sealing and rating before substituting.

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 6003-FAG model number is decoded

6003 is supplied open, without shields or seals, so the arrangement around it must supply and retain the lubricant. Within the extra-light 60xx section (diameter series 0 of ISO 15), multiplying bore code 17 by five gives the 17 mm bore; the 35 mm outside diameter and 10 mm width follow the same boundary-dimension plan. For a rotating inner ring on a 17 mm shaft under normal load, catalogue practice seats it on a j5 shaft fit with an H7 housing bore — confirm against the actual load direction and magnitude before committing. In the Schaeffler HR 1 catalogue this open execution carries the bare designation; protected variants are ordered separately with suffixes 2Z (steel shields), 2RZ (non-contact rubber seals) and 2RSR (lip-contact rubber seals).

Typical equipment & failure modes

Common applications

  • large gearboxes
  • industrial fans and blowers
  • hoists and winches
  • heavy conveyors

Known failure patterns

  • contamination wear from dust and dirt ingress through the open arrangement
  • lubricant starvation when no regreasing interval is maintained
  • false brinelling from vibration while the shaft is stationary
  • fretting corrosion on a loose shaft seat

Selection pitfalls — read before you substitute

  • Mount this 17 mm bore bearing by heating the inner ring (induction heater, max 120 °C) — never drive it home through the outer ring or balls, that brinells the raceways.
  • Choosing the 60xx extra-light section saves radial space at 17 mm bore, but the trade-off is rating: if the drive sees shock or frequent start-stop cycles, re-check the L10 life against a 6217 before committing to the smaller envelope.
  • Storage matters for open bearings: 6003-FAG leaves the factory with rust preventive only, so clean it and apply the service grease at assembly even if the rings look oily from the wrapper.
  • Open bearings tolerate the highest speeds in the 6000-series but need a defined regreasing interval; run-to-failure lubrication is the dominant cause of early failure in open 6003 units.
  • Vibration during standstill brinells the raceways of a 17 mm bearing at ball spacing; if the machine sits idle next to running equipment, turn the shaft over periodically or isolate the arrangement.
  • Axial location must clamp the ring face, not the seal area: a shoulder or circlip bearing on the seal side of the 10 mm-wide ring of 6003-FAG drags the lip and overheats it.
  • The open 6003 has no integral sealing; in the Schaeffler HR 1 catalogue the protected variants carry suffixes 2Z (two steel shields), 2RZ (two non-contact rubber seals) and 2RSR (two lip-contact rubber seals). Do not confuse FAG's 2RZ with a contact seal — the RZ lip does not touch the inner ring, which is why its speed capability stays close to the open bearing.
  • The 31000 r/min mechanical limiting speed puts 6003 at the top of the HR 1 deep-groove speed range (thermal reference speed 20300 r/min); at these speeds cage design and grease shear dominate — run open with oil-mist or air-over-oil lubrication and verify the thermal reference speed for the actual load before committing.
  • At 17 mm bore the 6003 sits in Schaeffler's small-bore range; HR 1 ships these sizes with a pressed steel or plastic cage and P0 tolerance as standard — for instrument or spindle accuracy order the P6/P5 variant explicitly, since P0 runout figures will not hold.
  • FAG rates 6003 at 6.4 kN dynamic (C) and 3.25 kN static (C0); this light-to-medium rating suits fractional-horsepower drives and instruments — verify the equivalent dynamic load stays well below C for conveying or gearbox duty with shock.
  • At only 38 g, 6003 is a lightweight FAG bearing that can be handled by hand; still press it onto the shaft with a sleeve against the inner ring — never through the balls or outer ring.
  • The 17×35×10 mm envelope of 6003 gives a D/d ratio of 2.06 and 9.0 mm radial section height — a heavy FAG section for high-load, lower-speed duty; specifying it in a high-rpm motor generates excess heat and shortens grease life, so prefer a 62/63-series there.
  • The 6.4/3.25 kN load ratings, mass 38 g here are Schaeffler HR 1 Rolling Bearings (Jan 2020) catalogue figures for 6003-FAG on the 17×35×10 mm ISO 15 envelope; internal geometry and ratings legitimately differ between brands, so re-verify before substituting another manufacturer's 6003 in a rated drive. Where FAG has since released an X-life version of this size, its expanded C/C0 ratings supersede the HR 1 print values quoted here.
  • FAG standard tolerance for this size is P0 (PN); P6/P5 precision executions exist for spindle-adjacent duty but carry different order numbers in the Schaeffler system — they are not a selectable sorting of standard stock.
  • Schaeffler's medias/eKatalog is the live source for the current execution of 6003: cage material, seal lip design and ratings can be revised between catalogue generations without any designation change.

Frequently asked questions

What are the dimensions of a 6003-FAG bearing?

A 6003-FAG deep-groove ball bearing has a 17 mm bore, 35 mm outer diameter and 10 mm width (0.669 × 1.378 × 0.394 in), per ISO 15 boundary dimensions. It is an open bearing with no seals or shields.

Are 6003 bearings from different brands interchangeable?

For boundary dimensions, yes: every brand's 6003 uses the same ISO 15 envelope (17×35×10 mm). Load ratings, limiting speeds, clearance, precision class and sealing design can differ, so verify those in the supplier catalogue when substituting.

What internal clearance does 6003-FAG have?

Unless a clearance suffix says otherwise, 6003-FAG is manufactured to normal (CN) radial internal clearance. Tight fits and hot shafts consume clearance in service — for those conditions order the C3 execution of 6003 and verify the residual clearance after mounting.

What is the FAG order number for an open 6003?

FAG lists the open 6003 under the bare designation 6003-FAG; protected versions use suffixes 2Z (steel shields), 2RZ (non-contact rubber seals) and 2RSR (lip-contact rubber seals) on the same 17 mm bore envelope.

What is the difference between FAG 2RZ and 2RSR seals?

2RZ is a non-contact rubber seal: minimal drag, speed close to the open bearing, not liquid-tight. 2RSR is a lip-contact seal: better protection against moisture and fine dust at the cost of speed and torque. Both keep the ISO 15 envelope of 6003-FAG.

Reviewed & verified by the MPN Base engineering desk against source catalog HR 1 Rolling Bearings (Jan 2020) on 2026-09-25. Read our editorial & correction policy.