L68149-L68111 bearing: complete specifications & equivalents
The L68149-L68111 is a ANSI ABMA 19.2 radial bearing sized 34.988 x 59.974 x 15.875 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 34.988 mm |
| Outer diameter D | 59.974 mm |
| Width B | 15.875 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 39 kN |
| Basic static load rating C0 | 47.5 kN |
| Limiting speed (mechanical) | 6100 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 179 g |
| Manufacturer designation | NTN 4T-L68149/L68111 |
| Standard | ANSI ABMA 19.2 |
| Catalog version | NTN 2203E 2026-09-25 |
| Last verified | 2026-10-01 |
Source: catalog reference (NTN 2203E 2026-09-25) · extracted 2026-10-01
Parameters extracted from the official NTN Ball and Roller Bearings catalogue (NTN 2203E 2026-09-25); NTN® is a trademark of NTN Corporation, used here for identification only — mpnbase is not an authorized NTN distributor. Boundary dimensions are ISO 15 interchangeable; current production values may differ, verify at ntnglobal.com.
Dimensions in inches & 4t-inch-series range
| Bore d | 1.377 in |
|---|---|
| Outer diameter D | 2.361 in |
| Width B | 0.625 in |
| ISO bore code | 49 |
| Radial section height (D−d)/2 | 12.5 mm |
| Smallest bore in 4t-inch-series | 12.7 mm |
| Largest outer diameter in 4t-inch-series | 260 mm |
| Width range across 4t-inch-series | 10.998–77.788 mm |
| Bore position in 4t-inch-series (smallest first) | 36 of 148 |
| Bore above smallest 4t-inch-series size | 22.288 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| L68149-110 | SKF | verify Commonly quoted cross reference; confirm against the target catalog before ordering. | Model-number interchange per ISO 15; confirm dimensions, sealing and ratings in the supplier catalogue. |
| L68149-111 | SKF | full Dimensions and internal design equivalent — standard interchange. | Identical ISO 15 envelope, seal and ratings band — standard interchange; re-verify precision class and clearance per supplier. |
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 L68149-L68111 model number is decoded
For an inch shaft of 34.988 mm carrying combined radial and thrust load, NTN lists 4T-L68149/L68111, a single-row 4T tapered roller set of 39 kN C and 47.5 kN C0 inside the 59.974 mm OD cup. Reading the designation: 4T-L68149/L68111 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the light L family lettering ties the pair to its boundary plan. Speed planning uses both catalogue columns: grease 6,100 r/min is the mechanical ceiling for 4T-L68149/L68111, oil 8,100 r/min with circulating oil — a 2,000 r/min margin at this size. Cup-side note for L68111: within the light L family tables the L68149 cone is listed against several cup options, and it is the cup that fixes the 59.974 mm OD and the 15.875 mm assembled width — quote the full L68149/L68111 pair, never the cone alone. Contact-pattern check with marking blue: a pattern biased to one roller end means the 34.988 mm pair is misadjusted and the set will edge-load in service.
Typical equipment & failure modes
Common applications
- construction-equipment pivot and wheel positions
- mining and quarry conveyor drive pulleys
- machine-tool headstocks on inch spindles
- pump and blower drive shafts with combined load
Known failure patterns
- rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries
- cup creep and housing fretting when the cup seat is cut too loose for the rotating load
- flaking on one cone only when a bent shaft loads the O/X pair unevenly
- cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling
- brinell marks on cone and cup raceways from impact during handling or hammer fitting
Selection pitfalls — read before you substitute
- Hub and pinion positions of this 34.988 mm class are adjusted in pairs; verify end play against the axle or gearbox drawing and re-torque after bedding-in instead of trusting the first setting on 4T-L68149/L68111.
- The light L family at 34.988 mm bore (59.974×15.875 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full L68149/L68111 reference at purchase.
- Open 4T-L68149/L68111 sets have no seals: a hub or gearbox needs external sealing or the 6,100 r/min grease figure is meaningless once water reaches the cone rib.
- Quote the full L68149/L68111 pair at ordering: the L68149 cone also ships against sibling cups, and a cup from another reference changes the 15.875 mm assembled width and the rating.
- Do not confuse T (15.875 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.
- The 39/47.5 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-L68149/L68111; internal geometry legitimately differs between inch-series makers, so re-verify ratings, adjustment and the exact cone/cup references before substituting another brand on a rated drive.
Frequently asked questions
What are the dimensions and catalogue ratings of NTN 4T-L68149/L68111?
4T-L68149/L68111 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 34.988 mm bore (1.377 in), 59.974 mm outside diameter and 15.875 mm assembled width T (2.361 × 0.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 39 kN, C0 47.5 kN, grease limiting speed 6,100 r/min, oil speed 8,100 r/min, mass about 179 g. It is an open, separable cone/cup set with a pressed-steel cage.
Are the cone and cup of 4T-L68149/L68111 interchangeable separately?
Yes — ABMA inch parts are individually interchangeable: the L68149 cone or the L68111 cup can be replaced by an identical reference from NTN or another ABMA-dimensioned maker. Pairing the cone with a different cup reference is a different catalogue row: OD, assembled T and the 39/47.5 kN ratings change with the cup.
What is the difference between 4T-L68149/L68111 and a metric ISO 355 tapered bearing?
4T-L68149/L68111 follows the ABMA inch boundary plan with cone/cup references; ISO 355 bearings use metric dimension-series numbers (302, 322, …). Even where a metric size looks close to 34.988×59.974×15.875 mm, the envelopes and contact angles differ — the two systems are not drop-in interchangeable; check every boundary value before substituting.
What does the 4T prefix on 4T-L68149/L68111 mean?
4T is NTN's tapered roller bearing quality mark, stamped on cone and cup in the factory. It identifies NTN's 4T programme and is not a dimension or variant code, so interchange lists quote the bare L68149/L68111 references; the 4T spelling is retained among this page's search aliases.
Why does 4T-L68149/L68111 list two speeds, 6,100 and 8,100 r/min?
The lower figure, 6,100 r/min, is the grease-lubricated limiting speed — the mechanical ceiling for the cage, rollers and cone-rib contact. With oil lubrication NTN rates 4T-L68149/L68111 at 8,100 r/min because oil removes rib-contact heat better. Real limits still depend on pair adjustment, oil flow and cooling.
Reviewed & verified by the MPN Base engineering desk against source catalog NTN 2203E 2026-09-25 on 2026-10-01. Read our editorial & correction policy.