537-532X-NTN bearing: complete specifications & equivalents
The 537-532X-NTN is a ANSI ABMA 19.2 radial bearing sized 50.8 x 107.95 x 36.512 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 50.8 mm |
| Outer diameter D | 107.95 mm |
| Width B | 36.512 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 157 kN |
| Basic static load rating C0 | 177 kN |
| Limiting speed (mechanical) | 3600 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 1550 g |
| Manufacturer designation | NTN 4T-537/532X |
| 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 in |
|---|---|
| Outer diameter D | 4.25 in |
| Width B | 1.437 in |
| ISO bore code | 37 |
| Radial section height (D−d)/2 | 28.6 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) | 64 of 148 |
| Bore above smallest 4t-inch-series size | 38.099999999999994 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 537-532X | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 50.8×107.95×36.512 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 537-532X-NTN model number is decoded
In NTN Ball and Roller Bearings CAT.No.2203E, the order number 4T-537/532X denotes the pure-numeric inch family of NTN inch tapered roller bearings — cone 537 and cup 532X delivered as a matched, separable pair of 50.8 mm bore and 107.95 mm outside diameter. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 537 identifies the cone of 50.8 mm (2 in) bore by catalogue lookup, and 532X fixes the 107.95 mm OD. Catalogue mass of the 4T-537/532X cone-plus-cup set is 1550 g; shaft and housing shoulders must carry that mass square to the axis during fitting. Housing fitment sequence for 4T-537/532X: press the 532X cup square into the 107.95 mm seat first, then bring the 537 cone (on its 50.8 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. NTN grades inch 4T bearings as open bearings without integral seals; at 50.8 mm bore the application supplies sealing and the grease fill or oil feed.
Typical equipment & failure modes
Common applications
- mining and quarry conveyor drive pulleys
- machine-tool headstocks on inch spindles
- pump and blower drive shafts with combined load
- truck and trailer axle hubs on inch-dimensioned axles
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 damage from a mounting blow transmitted through the roller complement
- fretting corrosion on a loose cone seat that creeps under rotating load
Selection pitfalls — read before you substitute
- Hub and pinion positions of this 50.8 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-537/532X.
- The pure-numeric inch family at 50.8 mm bore (107.95×36.512 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 537/532X reference at purchase.
- Do not confuse T (36.512 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.
- Open 4T-537/532X sets have no seals: a hub or gearbox needs external sealing or the 3,600 r/min grease figure is meaningless once water reaches the cone rib.
- Fit selection follows the rotating ring: a rotating cone on a 50.8 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.
- The 157/177 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-537/532X; 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-537/532X?
4T-537/532X is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 50.8 mm bore (2 in), 107.95 mm outside diameter and 36.512 mm assembled width T (4.25 × 1.437 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 157 kN, C0 177 kN, grease limiting speed 3,600 r/min, oil speed 4,800 r/min, mass about 1550 g. It is an open, separable cone/cup set with a pressed-steel cage.
Are the cone and cup of 4T-537/532X interchangeable separately?
Yes — ABMA inch parts are individually interchangeable: the 537 cone or the 532X 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 157/177 kN ratings change with the cup.
What is the difference between 4T-537/532X and a metric ISO 355 tapered bearing?
4T-537/532X 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 50.8×107.95×36.512 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-537/532X 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 537/532X references; the 4T spelling is retained among this page's search aliases.
Why does 4T-537/532X list two speeds, 3,600 and 4,800 r/min?
The lower figure, 3,600 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-537/532X at 4,800 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.