15103-15245 bearing: complete specifications & equivalents

The 15103-15245 is a ANSI ABMA 19.2 radial bearing sized 26.157 x 62 x 19.05 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.

Bearing dimension schematic Front view shows outer diameter D and bore d; side section shows width B. D = 62 mm d = 26.157 B = 19.05 mm side section front view
Principal dimensions: bore d 26.157 mm, outer diameter D 62 mm, width B 19.05 mm. Schematic, not to scale.

Specification table

ParameterValue
Brand NTN
Bore diameter d 26.157 mm
Outer diameter D 62 mm
Width B 19.05 mm
Material GCr15
Seal / shield open
Internal clearance CN
Tolerance class P0
Cage steel
Basic dynamic load rating C 52 kN
Basic static load rating C0 54 kN
Limiting speed (mechanical) 6100 rpm
Operating temperature -40 to +120 °C
Mass 300 g
Manufacturer designation NTN 4T-15103/15245
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 1.03 in
Outer diameter D 2.441 in
Width B 0.75 in
ISO bore code —
Radial section height (D−d)/2 17.9 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) 20 of 148
Bore above smallest 4t-inch-series size 13.457 mm

Cross references & equivalents

Equivalent modelBrandMatch levelNote
15103 ISO 15 full
Dimensions and internal design equivalent — standard interchange.
ISO 15 boundary-dimension envelope; brand-specific OEM equivalents (NSK/FAG/NTN) pending multi-source data.

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 15103-15245 model number is decoded

NTN supplies this 1.03 in (26.157 mm) shaft position as 4T-15103/15245: cone 15103, cup 15245, profiled rollers and a pressed-steel cage, rated 52 kN basic dynamic and 54 kN static. Reading the designation: 4T-15103/15245 follows the ABMA inch convention — the number before the slash is the cone (inner ring with roller set and cage), the number after the slash is the cup (outer ring), and the pure-numeric inch family lettering ties the pair to its boundary plan. The 17.9 mm radial section over the 26.157 mm bore positions the contact line of the pair; abutment shoulders and spacers are dimensioned from that geometry, not from the bore alone. Housing fitment sequence for 4T-15103/15245: press the 15245 cup square into the 62 mm seat first, then bring the 15103 cone (on its 26.157 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Mount the 26.157 mm cone with an induction heater (max 120 °C) and press the 62 mm cup with a sleeve; driving either ring through the rollers brinells the raceways.

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

  • cone-rib and roller large-end smearing when the adjusted pair runs with preload but starved lubricant film
  • 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
  • cage fatigue when the pair runs continuously near the grease limiting speed without oil cooling
  • fretting corrosion on a loose cone seat that creeps under rotating load

Selection pitfalls — read before you substitute

  • Hub and pinion positions of this 26.157 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-15103/15245.
  • The pure-numeric inch family at 26.157 mm bore (62×19.05 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 15103/15245 reference at purchase.
  • Do not confuse T (19.05 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.
  • Replacing one half of an adjusted pair without resetting end play negates the 19.05 mm T logic: re-adjust the set and re-verify the contact pattern rather than reusing the old spacer stack.
  • Do not confuse T (19.05 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.
  • The 52/54 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-15103/15245; 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-15103/15245?

4T-15103/15245 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 26.157 mm bore (1.03 in), 62 mm outside diameter and 19.05 mm assembled width T (2.441 × 0.75 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 52 kN, C0 54 kN, grease limiting speed 6,100 r/min, oil speed 8,200 r/min, mass about 300 g. It is an open, separable cone/cup set with a pressed-steel cage.

Are the cone and cup of 4T-15103/15245 interchangeable separately?

Yes — ABMA inch parts are individually interchangeable: the 15103 cone or the 15245 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 52/54 kN ratings change with the cup.

What is the difference between 4T-15103/15245 and a metric ISO 355 tapered bearing?

4T-15103/15245 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 26.157×62×19.05 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-15103/15245 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 15103/15245 references; the 4T spelling is retained among this page's search aliases.

Why does 4T-15103/15245 list two speeds, 6,100 and 8,200 r/min?

The lower figure, 6,100 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-15103/15245 at 8,200 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.