665-653-NTN bearing: complete specifications & equivalents
The 665-653-NTN is a ANSI ABMA 19.2 radial bearing sized 85.725 x 146.05 x 41.275 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.
Specification table
| Parameter | Value |
|---|---|
| Brand | NTN |
| Bore diameter d | 85.725 mm |
| Outer diameter D | 146.05 mm |
| Width B | 41.275 mm |
| Material | GCr15 |
| Seal / shield | open |
| Internal clearance | CN |
| Tolerance class | P0 |
| Cage | steel |
| Basic dynamic load rating C | 228 kN |
| Basic static load rating C0 | 295 kN |
| Limiting speed (mechanical) | 2500 rpm |
| Operating temperature | -40 to +120 °C |
| Mass | 2650 g |
| Manufacturer designation | NTN 4T-665/653 |
| 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 | 3.375 in |
|---|---|
| Outer diameter D | 5.75 in |
| Width B | 1.625 in |
| ISO bore code | — |
| Radial section height (D−d)/2 | 30.2 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) | 104 of 148 |
| Bore above smallest 4t-inch-series size | 73.02499999999999 mm |
Cross references & equivalents
| Equivalent model | Brand | Match level | Note |
|---|---|---|---|
| 665-653 | SKF | partial Main dimensions match; tolerances, seals or internal clearance differ. | Same 85.725×146.05×41.275 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 665-653-NTN model number is decoded
4T-665/653 is the NTN 4T catalogue entry for a 85.725×146.05×41.275 mm inch tapered roller bearing — an ABMA-dimensioned cone/cup set, not an ISO 355 metric bearing, even though the table quotes metric equivalents. Cone and cup of 4T-665/653 are separately stocked parts: a worn 653 cup can be replaced against the existing 665 cone, provided the new cup carries the identical reference — pairing across references changes the 41.275 mm assembled width and the rating. Speed planning uses both catalogue columns: grease 2,500 r/min is the mechanical ceiling for 4T-665/653, oil 3,300 r/min with circulating oil — a 800 r/min margin at this size. Cup-side note for 653: within the pure-numeric inch family tables the 665 cone is listed against several cup options, and it is the cup that fixes the 146.05 mm OD and the 41.275 mm assembled width — quote the full 665/653 pair, never the cone alone. Back-to-back (O) and face-to-face (X) arrangements of two 4T-665/653 sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.
Typical equipment & failure modes
Common applications
- heavy truck and bus drive-axle differentials
- plant gearboxes on inch-dimensioned shaft lines
- large conveyor head pulleys in bulk-handling plant
- paper-machine and calender roll supports
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
- 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 85.725 mm cone by induction heating (max 120 °C) and the 146.05 mm cup with a press sleeve; at 2650 g a cocked ring brinells the raceway directly.
- The pure-numeric inch family at 85.725 mm bore (146.05×41.275 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 665/653 reference at purchase.
- Fit selection follows the rotating ring: a rotating cone on a 85.725 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.
- Quote the full 665/653 pair at ordering: the 665 cone also ships against sibling cups, and a cup from another reference changes the 41.275 mm assembled width and the rating.
- Fit selection follows the rotating ring: a rotating cone on a 85.725 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.
- The 228/295 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-665/653; 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-665/653?
4T-665/653 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 85.725 mm bore (3.375 in), 146.05 mm outside diameter and 41.275 mm assembled width T (5.75 × 1.625 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 228 kN, C0 295 kN, grease limiting speed 2,500 r/min, oil speed 3,300 r/min, mass about 2650 g. It is an open, separable cone/cup set with a pressed-steel cage.
Are the cone and cup of 4T-665/653 interchangeable separately?
Yes — ABMA inch parts are individually interchangeable: the 665 cone or the 653 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 228/295 kN ratings change with the cup.
What is the difference between 4T-665/653 and a metric ISO 355 tapered bearing?
4T-665/653 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 85.725×146.05×41.275 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-665/653 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 665/653 references; the 4T spelling is retained among this page's search aliases.
Why does 4T-665/653 list two speeds, 2,500 and 3,300 r/min?
The lower figure, 2,500 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-665/653 at 3,300 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.