LM11749-LM11710 bearing: complete specifications & equivalents
The LM11749-LM11710 is a ANSI ABMA 19.2 radial bearing sized 17.462 x 39.878 x 13.843 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 17.462 mm |
| Outer diameter D | 39.878 mm |
| Width B | 13.843 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 26.4 kN |
| Basic static load rating C0 | 24.2 kN |
| Limiting speed (mechanical) | 10000 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 84 g |
| Manufacturer designation | NTN 4T-LM11749/LM11710 |
| 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 | 0.687 in |
|---|---|
| Outer diameter D | 1.57 in |
| Width B | 0.545 in |
| ISO bore code | 49 |
| Radial section height (D−d)/2 | 11.2 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) | 5 of 148 |
| Bore above smallest 4t-inch-series size | 4.7620000000000005 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| LM11749-710 | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 17.462×39.878×13.843 mm envelope per ISO 15; catalogue load ratings differ by >10% — re-rate the application before substituting. |
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 LM11749-LM11710 model number is decoded
In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-LM11749/LM11710 denotes the light-medium LM family of NTN inch tapered roller bearings — cone LM11749 and cup LM11710 delivered as a matched, separable pair of 17.462 mm bore and 39.878 mm outside diameter. The 4T prefix is NTN's tapered roller quality mark stamped on both parts; it is a brand mark, not a size code, so cross-references quote LM11749/LM11710 without it. Two single-row inch sets are normally mounted as an adjusted O or X pair; the 13.843 mm T of each 4T-LM11749/LM11710 enters the spacer calculation, so the tolerance on assembled width matters as much as the bore fit. Cup-side note for LM11710: within the light-medium LM family tables the LM11749 cone is listed against several cup options, and it is the cup that fixes the 39.878 mm OD and the 13.843 mm assembled width — quote the full LM11749/LM11710 pair, never the cone alone. Contact-pattern check with marking blue: a pattern biased to one roller end means the 17.462 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
- rib-face scoring when the thrust share of the combined load exceeds what the cone rib of this size carries
- false brinelling on a stationary pair exposed to vibration during transport or standby
- preload loss and noise after one bearing of the adjusted pair is replaced without resetting end play
- 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
- At 17.462 mm (0.687 in) bore the thin cone and cup distort under an over-tight shaft nut; set the 4T-LM11749/LM11710 pair with a dial indicator on end play rather than by locknut feel.
- The light-medium LM family at 17.462 mm bore (39.878×13.843 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full LM11749/LM11710 reference at purchase.
- Do not confuse T (13.843 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.
- Never drive the 39.878 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.
- Fit selection follows the rotating ring: a rotating cone on a 17.462 mm shaft takes a j5/k5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.
- The 26.4/24.2 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-LM11749/LM11710; 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-LM11749/LM11710?
4T-LM11749/LM11710 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 17.462 mm bore (0.687 in), 39.878 mm outside diameter and 13.843 mm assembled width T (1.57 × 0.545 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 26.4 kN, C0 24.2 kN, grease limiting speed 10,000 r/min, oil speed 13,000 r/min, mass about 84 g. It is an open, separable cone/cup set with a pressed-steel cage.
Are the cone and cup of 4T-LM11749/LM11710 interchangeable separately?
Yes — ABMA inch parts are individually interchangeable: the LM11749 cone or the LM11710 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 26.4/24.2 kN ratings change with the cup.
What is the difference between 4T-LM11749/LM11710 and a metric ISO 355 tapered bearing?
4T-LM11749/LM11710 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 17.462×39.878×13.843 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-LM11749/LM11710 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 LM11749/LM11710 references; the 4T spelling is retained among this page's search aliases.
Why does 4T-LM11749/LM11710 list two speeds, 10,000 and 13,000 r/min?
The lower figure, 10,000 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-LM11749/LM11710 at 13,000 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.