LM11949-LM11910 bearing: complete specifications & equivalents
The LM11949-LM11910 is a ANSI ABMA 19.2 radial bearing sized 19.05 x 45.237 x 15.494 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 19.05 mm |
| Outer diameter D | 45.237 mm |
| Width B | 15.494 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 31.5 kN |
| Basic static load rating C0 | 28.6 kN |
| Limiting speed (mechanical) | 8900 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 123 g |
| Manufacturer designation | NTN 4T-LM11949/LM11910 |
| 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 | 0.75 in |
|---|---|
| Outer diameter D | 1.781 in |
| Width B | 0.61 in |
| ISO bore code | 49 |
| Radial section height (D−d)/2 | 13.1 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) | 6 of 148 |
| Bore above smallest 4t-inch-series size | 6.350000000000001 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| LM11949-910 | 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 LM11949-LM11910 model number is decoded
4T-LM11949/LM11910 is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 19.05×45.237×15.494 mm (assembled width T), for a shaft of about 19.05 mm (0.75 in). Cone and cup of 4T-LM11949/LM11910 are separately stocked parts: a worn LM11910 cup can be replaced against the existing LM11949 cone, provided the new cup carries the identical reference — pairing across references changes the 15.494 mm assembled width and the rating. Contact-angle geometry of the light-medium LM family gives 4T-LM11949/LM11910 its radial/axial load split — at 31.5/28.6 kN the static rating is about 0.91× C, typical of inch tapered sets proportioned for combined duty. The printed 31.5/28.6 kN ratings belong to the assembled LM11949+LM11910 pair; a sibling row using the same cone with a different cup carries its own rating row because the raceway track shifts with the cup. Contact-pattern check with marking blue: a pattern biased to one roller end means the 19.05 mm pair is misadjusted and the set will edge-load in service.
Typical equipment & failure modes
Common applications
- utility-vehicle differential and pinion supports
- small machine-tool feed and spindle counter-supports
- light trailer and boat-trailer wheel hubs
- small agricultural implement wheels and auger drives
Known failure patterns
- cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film
- 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 damage from a mounting blow transmitted through the roller complement
- water-induced pitting when the open bearing sees washdown without external seals
Selection pitfalls — read before you substitute
- At 19.05 mm (0.75 in) bore the thin cone and cup distort under an over-tight shaft nut; set the 4T-LM11949/LM11910 pair with a dial indicator on end play rather than by locknut feel.
- The light-medium LM family at 19.05 mm bore (45.237×15.494 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full LM11949/LM11910 reference at purchase.
- Replacing one half of an adjusted pair without resetting end play negates the 15.494 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.
- Open 4T-LM11949/LM11910 sets have no seals: a hub or gearbox needs external sealing or the 8,900 r/min grease figure is meaningless once water reaches the cone rib.
- Never drive the 45.237 mm cup home through the rollers: fitting force goes through the ring faces only, or brinell marks release as noise within the first running hours.
- The 31.5/28.6 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-LM11949/LM11910; 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-LM11949/LM11910?
4T-LM11949/LM11910 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 19.05 mm bore (0.75 in), 45.237 mm outside diameter and 15.494 mm assembled width T (1.781 × 0.61 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 31.5 kN, C0 28.6 kN, grease limiting speed 8,900 r/min, oil speed 12,000 r/min, mass about 123 g. It is an open, separable cone/cup set with a pressed-steel cage.
Are the cone and cup of 4T-LM11949/LM11910 interchangeable separately?
Yes — ABMA inch parts are individually interchangeable: the LM11949 cone or the LM11910 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 31.5/28.6 kN ratings change with the cup.
What is the difference between 4T-LM11949/LM11910 and a metric ISO 355 tapered bearing?
4T-LM11949/LM11910 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 19.05×45.237×15.494 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-LM11949/LM11910 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 LM11949/LM11910 references; the 4T spelling is retained among this page's search aliases.
Why does 4T-LM11949/LM11910 list two speeds, 8,900 and 12,000 r/min?
The lower figure, 8,900 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-LM11949/LM11910 at 12,000 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.