L812148-L812111 bearing: complete specifications & equivalents
The L812148-L812111 is a ANSI ABMA 19.2 radial bearing sized 66.675 x 103.213 x 17.602 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 66.675 mm |
| Outer diameter D | 103.213 mm |
| Width B | 17.602 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 66.5 kN |
| Basic static load rating C0 | 78 kN |
| Limiting speed (mechanical) | 3300 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 480 g |
| Manufacturer designation | NTN 4T-L812148/L812111 |
| 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 | 2.625 in |
|---|---|
| Outer diameter D | 4.064 in |
| Width B | 0.693 in |
| ISO bore code | 48 |
| Radial section height (D−d)/2 | 18.3 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) | 84 of 148 |
| Bore above smallest 4t-inch-series size | 53.974999999999994 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| L812148 | ISO 15 | full Dimensions and internal design equivalent — standard interchange. | ISO 15 boundary-dimension envelope; brand-specific OEM equivalents (NSK/FAG/NTN) pending multi-source data. |
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 L812148-L812111 model number is decoded
4T-L812148/L812111 belongs to the NTN inch 4T tapered roller range (light L family); cone and cup are ordered by their own references and are individually interchangeable with like-numbered parts. Cone and cup of 4T-L812148/L812111 are separately stocked parts: a worn L812111 cup can be replaced against the existing L812148 cone, provided the new cup carries the identical reference — pairing across references changes the 17.602 mm assembled width and the rating. The 1.0 kN of dynamic capacity per millimetre of bore summarises the 66.5 kN rating over the 66.675 mm bore — sanity-check any interchange candidate against this ratio and the 17.602 mm T. Cup-side note for L812111: within the light L family tables the L812148 cone is listed against several cup options, and it is the cup that fixes the 103.213 mm OD and the 17.602 mm assembled width — quote the full L812148/L812111 pair, never the cone alone. Mount the 66.675 mm cone with an induction heater (max 120 °C) and press the 103.213 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.
Typical equipment & failure modes
Common applications
- off-highway and forestry machine axles
- marine winch and deck-machinery shafts
- crusher and screening-plant eccentric shafts
- heavy truck and bus drive-axle differentials
Known failure patterns
- rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries
- flaking on one cone only when a bent shaft loads the O/X pair unevenly
- cup creep and housing fretting when the cup seat is cut too loose for the rotating load
- cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling
- rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load
Selection pitfalls — read before you substitute
- Mount the 66.675 mm cone by induction heating (max 120 °C) and the 103.213 mm cup with a press sleeve; at 480 g a cocked ring brinells the raceway directly.
- The light L family at 66.675 mm bore (103.213×17.602 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full L812148/L812111 reference at purchase.
- Open 4T-L812148/L812111 sets have no seals: a hub or gearbox needs external sealing or the 3,300 r/min grease figure is meaningless once water reaches the cone rib.
- Grease packs must leave free volume inside the 17.602 mm-wide set; over-greasing a pair churning near the oil-band speed of 4,400 r/min raises temperature and destroys the setting.
- Fit selection follows the rotating ring: a rotating cone on a 66.675 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.
- The 66.5/78 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-L812148/L812111; 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-L812148/L812111?
4T-L812148/L812111 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 66.675 mm bore (2.625 in), 103.213 mm outside diameter and 17.602 mm assembled width T (4.064 × 0.693 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 66.5 kN, C0 78 kN, grease limiting speed 3,300 r/min, oil speed 4,400 r/min, mass about 480 g. It is an open, separable cone/cup set with a pressed-steel cage.
Are the cone and cup of 4T-L812148/L812111 interchangeable separately?
Yes — ABMA inch parts are individually interchangeable: the L812148 cone or the L812111 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 66.5/78 kN ratings change with the cup.
What is the difference between 4T-L812148/L812111 and a metric ISO 355 tapered bearing?
4T-L812148/L812111 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 66.675×103.213×17.602 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-L812148/L812111 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 L812148/L812111 references; the 4T spelling is retained among this page's search aliases.
Why does 4T-L812148/L812111 list two speeds, 3,300 and 4,400 r/min?
The lower figure, 3,300 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-L812148/L812111 at 4,400 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.