LM29748-LM29710 bearing: complete specifications & equivalents
The LM29748-LM29710 is a ANSI ABMA 19.2 radial bearing sized 38.1 x 65.088 x 18.034 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 38.1 mm |
| Outer diameter D | 65.088 mm |
| Width B | 18.034 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 48 kN |
| Basic static load rating C0 | 57 kN |
| Limiting speed (mechanical) | 5500 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 227 g |
| Manufacturer designation | NTN 4T-LM29748/LM29710 |
| 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 | 1.5 in |
|---|---|
| Outer diameter D | 2.563 in |
| Width B | 0.71 in |
| ISO bore code | 48 |
| Radial section height (D−d)/2 | 13.5 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) | 42 of 148 |
| Bore above smallest 4t-inch-series size | 25.400000000000002 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| LM29748-710 | 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 LM29748-LM29710 model number is decoded
The NTN 2203E inch table prints 4T-LM29748/LM29710 at 38.1 mm bore (1.5 in), 65.088 mm cup OD and 18.034 mm assembled T, with a grease limiting speed of 5,500 r/min and an oil ceiling of 7,400 r/min. Letter prefixes inherited from the inch convention mark the load family: LM reads as light-medium, HM as heavy-medium, LL as extra-light, J-prefixed codes as metric-envelope families — LM29748 sits in the light-medium LM family. The 13.5 mm radial section over the 38.1 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Cup-side note for LM29710: within the light-medium LM family tables the LM29748 cone is listed against several cup options, and it is the cup that fixes the 65.088 mm OD and the 18.034 mm assembled width — quote the full LM29748/LM29710 pair, never the cone alone. Fillet radii must clear the chamfers of the LM29748 cone and LM29710 cup; undercut shoulders seat the rings fully instead of bridging on a radius.
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
- preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play
- false brinelling on a stationary pair exposed to vibration during transport or standby
- pressed-steel cage pocket wear from roller skid at light radial load and high speed
- rolling-contact fatigue spalling after the catalogue L10 life at the actual combined load
Selection pitfalls — read before you substitute
- Hub and pinion positions of this 38.1 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-LM29748/LM29710.
- The light-medium LM family at 38.1 mm bore (65.088×18.034 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full LM29748/LM29710 reference at purchase.
- Open 4T-LM29748/LM29710 sets have no seals: a hub or gearbox needs external sealing or the 5,500 r/min grease figure is meaningless once water reaches the cone rib.
- Inch and metric bores collide on paper — 38.1 mm is 1.5 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.
- Inch and metric bores collide on paper — 38.1 mm is 1.5 in, not a round metric size; a metric bearing that seems 0.1 mm off will not seat on the inch shaft.
- The 48/57 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-LM29748/LM29710; 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-LM29748/LM29710?
4T-LM29748/LM29710 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 38.1 mm bore (1.5 in), 65.088 mm outside diameter and 18.034 mm assembled width T (2.563 × 0.71 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 48 kN, C0 57 kN, grease limiting speed 5,500 r/min, oil speed 7,400 r/min, mass about 227 g. It is an open, separable cone/cup set with a pressed-steel cage.
Are the cone and cup of 4T-LM29748/LM29710 interchangeable separately?
Yes — ABMA inch parts are individually interchangeable: the LM29748 cone or the LM29710 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 48/57 kN ratings change with the cup.
What is the difference between 4T-LM29748/LM29710 and a metric ISO 355 tapered bearing?
4T-LM29748/LM29710 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 38.1×65.088×18.034 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-LM29748/LM29710 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 LM29748/LM29710 references; the 4T spelling is retained among this page's search aliases.
Why does 4T-LM29748/LM29710 list two speeds, 5,500 and 7,400 r/min?
The lower figure, 5,500 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-LM29748/LM29710 at 7,400 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.