390-394A bearing: complete specifications & equivalents

Specification table

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.

Cross references & equivalents

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 390-394A model number is decoded

4T-390/394A is an NTN inch-series single-row tapered roller bearing: a separable cone-and-cup pair on the ABMA inch boundary plan, 57.15×110×22 mm (assembled width T), for a shaft of about 57.15 mm (2.25 in). Reading the designation: 4T-390/394A 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 1.7 kN of dynamic capacity per millimetre of bore summarises the 99.5 kN rating over the 57.15 mm bore — sanity-check any interchange candidate against this ratio and the 22 mm T. Housing fitment sequence for 4T-390/394A: press the 394A cup square into the 110 mm seat first, then bring the 390 cone (on its 57.15 mm shaft) into adjustment — the two references are separate engineering parts that happen to ship as one set. Back-to-back (O) and face-to-face (X) arrangements of two 4T-390/394A sets react differently to shaft bending; choose the orientation for the moment load before locking shoulder geometry.

Typical equipment & failure modes

Selection pitfalls — read before you substitute

• Mount the 57.15 mm cone by induction heating (max 120 °C) and the 110 mm cup with a press sleeve; at 961 g a cocked ring brinells the raceway directly.
• The pure-numeric inch family at 57.15 mm bore (110×22 mm assembled) is one of several inch families sharing similar bores; cross-series swaps change OD, T and contact angle, so match the full 390/394A reference at purchase.
• Do not confuse T (22 mm, the assembled cone-plus-cup width) with the cone width when drawing spacers; an abutment sized to T leaves the cup unseated.
• Fit selection follows the rotating ring: a rotating cone on a 57.15 mm shaft takes a k5/m5 seat, and a rotating cup reverses the logic — decide from the load diagram, not from habit.
• An unloaded 4T-390/394A near 3,200 r/min lets rollers skid and smear the cone rib; spring-preload lightly loaded high-speed pairs.
• The 99.5/120 kN ratings here are NTN Ball and Roller Bearings CAT.No.2203E figures for 4T-390/394A; 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.