6008-FAG bearing: complete specifications & equivalents

Specification table

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.

Cross references & equivalents

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 6008-FAG model number is decoded

6008 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 08 by five gives the 40 mm bore; the 68 mm outside diameter and 15 mm width follow the same boundary-dimension plan. For a rotating inner ring on a 40 mm shaft under normal load, catalogue practice seats it on a k5 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

Selection pitfalls — read before you substitute

• At a 40 mm bore, a shaft-seat burr or an overtight setscrew can score the thin inner ring of 6008-FAG; check shaft finish and runout (target Ra ≤ 1.6 µm) before pressing it home.
• Choosing the 60xx extra-light section saves radial space at 40 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 6208 before committing to the smaller envelope.
• The open 6008-FAG has no lubricant retention: grease escapes and contaminants migrate straight into the 40×68×15 mm raceway, so specify a sealed arrangement for dusty or washdown duty.
• 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 6008 units.
• Do not quieten a noisy bearing by preloading it: the 6000-series is a deep-groove design, not angular-contact; axial preload raises temperature and shortens grease life.
• Grease compatibility is not guaranteed between fills: mixing lithium and polyurea thickeners in a 6000-series position can soften the mixture and leak — clean out the old fill before switching grease types.
• The open 6008 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.
• FAG rates 6008 at 14600 r/min mechanical limiting speed (thermal reference speed 10600 r/min) — electric-motor territory; prefer the open or 2Z execution (sealed 2RSR variants lose roughly a third of the thermal speed) and confirm grease life at the reference speed for continuous running.
• The 40 mm bore puts 6008 in Schaeffler's general-purpose industrial range; the standard cage and CN clearance cover most electric-motor and pump duty, and FAG's X-life generation of these sizes carries higher ratings than legacy HR 1 printings — check the current eKatalog listing before reordering.
• At 17.8 kN dynamic load rating (C) and 11.5 kN static (C0), 6008 is a medium-load FAG bearing for most electric-motor and pump duty; check the static safety factor against C0 for preloaded or thrust-loaded arrangements.
• At 192 g, 6008 is light enough for hand assembly but should be pressed on with a fitting sleeve against the inner ring; do not strike the outer ring or cage with a hammer.
• The 40×68×15 mm envelope of 6008 gives a D/d ratio of 1.70 and 14.0 mm radial section height — a standard FAG medium section balancing load capacity and speed; the standard cage is adequate up to the listed speeds and C3 clearance is the common hot-shaft choice.
• The 17.8/11.5 kN load ratings, mass 192 g here are Schaeffler HR 1 Rolling Bearings (Jan 2020) catalogue figures for 6008-FAG on the 40×68×15 mm ISO 15 envelope; internal geometry and ratings legitimately differ between brands, so re-verify before substituting another manufacturer's 6008 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.
• For hot shafts above roughly 100 °C continuous, consult Schaeffler about seal material and grease options for the 2RSR execution of 6008; the standard NBR lip is the economical general-duty choice, not the high-temperature one.
• Mixing old and new FAG generations of the same designation in one arrangement is dimensionally acceptable, but where ratings matter — preloaded or matched sets — order both positions from the same generation and lot.