3382-3321 bearing: complete specifications & equivalents

The 3382-3321 is a ANSI ABMA 19.2 radial bearing sized 39.688 x 77.534 x 29.37 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 = 77.534 mm d = 39.688 B = 29.37 mm side section front view
Principal dimensions: bore d 39.688 mm, outer diameter D 77.534 mm, width B 29.37 mm. Schematic, not to scale.

Specification table

ParameterValue
Brand NTN
Bore diameter d 39.688 mm
Outer diameter D 77.534 mm
Width B 29.37 mm
Material GCr15
Seal / shield open
Internal clearance CN
Tolerance class P0
Cage steel
Basic dynamic load rating C 105 kN
Basic static load rating C0 112 kN
Limiting speed (mechanical) 4800 rpm
Operating temperature -40 to +120 °C
Mass 669 g
Manufacturer designation NTN 4T-3382/3321
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 1.563 in
Outer diameter D 3.053 in
Width B 1.156 in
ISO bore code —
Radial section height (D−d)/2 18.9 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) 43 of 148
Bore above smallest 4t-inch-series size 26.988000000000003 mm

Cross references & equivalents

Equivalent modelBrandMatch levelNote
3382-3339 NTN partial
Main dimensions match; tolerances, seals or internal clearance differ.
Same NTN cone 4T-3382 paired with a different cup (3339): cone interchangeable, cup differs — OD, assembled width T and ratings follow the cup. Verify the full cone/cup reference 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 3382-3321 model number is decoded

NTN supplies this 1.563 in (39.688 mm) shaft position as 4T-3382/3321: cone 3382, cup 3321, profiled rollers and a pressed-steel cage, rated 105 kN basic dynamic and 112 kN static. Unlike ISO 355 metric numbers, this ABMA code does not encode the bore arithmetically: 3382 identifies the cone of 39.688 mm (1.563 in) bore by catalogue lookup, and 3321 fixes the 77.534 mm OD. Speed planning uses both catalogue columns: grease 4,800 r/min is the mechanical ceiling for 4T-3382/3321, oil 6,400 r/min with circulating oil — a 1,600 r/min margin at this size. The printed 105/112 kN ratings belong to the assembled 3382+3321 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. After bedding-in, re-check the end play of the adjusted 4T-3382/3321 pair — initial seating of the ring faces relaxes the setting slightly.

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

  • 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
  • pressed-steel cage pocket wear from roller skid at light radial load and high speed
  • water-induced pitting when the open bearing sees washdown without external seals

Selection pitfalls — read before you substitute

  • Hub and pinion positions of this 39.688 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-3382/3321.
  • The pure-numeric inch family at 39.688 mm bore (77.534×29.37 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 3382/3321 reference at purchase.
  • Grease packs must leave free volume inside the 29.37 mm-wide set; over-greasing a pair churning near the oil-band speed of 6,400 r/min raises temperature and destroys the setting.
  • Fit selection follows the rotating ring: a rotating cone on a 39.688 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 3382/3321 pair at ordering: the 3382 cone also ships against sibling cups, and a cup from another reference changes the 29.37 mm assembled width and the rating.
  • The 105/112 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-3382/3321; 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-3382/3321?

4T-3382/3321 is an inch-series single-row tapered roller bearing to the ABMA boundary plan: 39.688 mm bore (1.563 in), 77.534 mm outside diameter and 29.37 mm assembled width T (3.053 × 1.156 in). From NTN Ball and Roller Bearings CAT.No.2203E: C 105 kN, C0 112 kN, grease limiting speed 4,800 r/min, oil speed 6,400 r/min, mass about 669 g. It is an open, separable cone/cup set with a pressed-steel cage.

Are the cone and cup of 4T-3382/3321 interchangeable separately?

Yes — ABMA inch parts are individually interchangeable: the 3382 cone or the 3321 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 105/112 kN ratings change with the cup.

What is the difference between 4T-3382/3321 and a metric ISO 355 tapered bearing?

4T-3382/3321 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 39.688×77.534×29.37 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-3382/3321 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 3382/3321 references; the 4T spelling is retained among this page's search aliases.

Why does 4T-3382/3321 list two speeds, 4,800 and 6,400 r/min?

The lower figure, 4,800 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-3382/3321 at 6,400 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.