3984 Bearing Dimensions
3984 inch tapered roller bearing cone, paired with the 3920 cup: 66.675 mm (2.625 in) bore, 112.712 mm OD, 30.162 mm width (FULI catalog). Quote.
3984 specifications
| Cone bore d | 66.675 mm (2.625 in) |
|---|---|
| Cone width B | 30.048 mm |
| Matching cup | 3920 |
| Cup outside diameter D | 112.712 mm (4.437 in) |
| Total width T | 30.162 mm (1.187 in) — assembled width of cup and cone |
| Seal / shield options | Open (cup and cone, no seals) |
| Material | GCr15 chrome bearing steel (rings and rolling elements) |
| Radial clearance | Set during mounting (adjustable, not a C-class value) |
| Load ratings | See the cone and cup pairs table below |
3984 cone and cup pairs
| Cone | Cup | Bore d | OD D | Width T | Cr (kN) | C0r (kN) |
|---|---|---|---|---|---|---|
| 3984 | 3920 | 66.675 mm (2.625 in) | 112.712 mm (4.437 in) | 30.162 mm (1.187 in) | 120.2 | 175.7 |
Dimensions from FULI's catalog. A cone (inner ring with rollers and cage) and a cup (outer ring) make up one bearing; the pairs above are the matching numbers listed in FULI's catalog. Values from FULI's catalog; confirm for your application.
How to read the 3984 designation
| Segment | Meaning |
|---|---|
| 3984 | Designation breakdown not available for this model. |
3984 interchange
3984 is an inch tapered roller bearing cone. Inch tapered roller bearings are ordered by cone number and cup number. Most makers use the same cone and cup numbers for the same size, but always check the cup number as well. Send us the numbers on your old bearing and we confirm the match before quoting.
Brand names are trademarks of their respective owners. FULI is not affiliated with, authorized by or endorsed by these companies. Part numbers are shown for interchange reference only. FULI dimensions, load ratings and speeds come from the FULI catalog.
3984 compared with nearby cone sizes
The 3984 cone has a 66.675 mm (2.625 in) bore and a cone width of 30.048 mm. FULI's catalog pairs it with cup 3920 (112.712 mm outside diameter, 30.162 mm total width).
The next smaller cone on this site is 395S, with a 66.675 mm bore (0 mm smaller) and cup 394A.
The next larger is HM212049, with a 66.675 mm bore (0 mm larger) and cup HM212011.
Cup 3920 is also listed with JM511945, so the same housing bore can take a different cone if the shaft size changes.
The metric tapered bearing on this site closest in bore is 33013 (65 × 100 × 27 mm). Its sizes differ from the 3984 pair, so the two are not interchangeable; it is given only as a size reference.
| Cone | Cup | d × D × T | Cr (kN) |
|---|---|---|---|
| 39590 | 39520 | 66.675 × 112.712 × 30.162 mm | 144.9 |
| 395A | 394A | 66.675 × 110 × 22 mm | 88.6 |
| 395S | 394A | 66.675 × 110 × 22 mm | 88.6 |
| 3984 | 3920 | 66.675 × 112.712 × 30.162 mm | 120.2 |
| HM212049 | HM212011 | 66.675 × 122.238 × 38.1 mm | 191.3 |
| 33287 | 33462 | 73.025 × 117.475 × 30.162 mm | 128 |
| 6461A | 6420 | 76.2 × 149.225 × 53.975 mm | — |
Sizes and Cr from FULI's catalog; — = not listed on this site.
3984 load ratings
3984/3920 has a dynamic load rating Cr of 120.2 kN and a static rating C0r of 175.7 kN in FULI's catalog. The ratings belong to the cone and cup as a pair; a different cup changes them.
Speed limits and weights for inch cones are not listed in the catalog; ask us and we send them with the quotation.
Values from FULI's catalog; confirm for your application.
3984 size in inches and millimetres
3984 is made to inch sizes. The 66.675 mm bore is 2-5/8 in. The millimetre values in the catalog are conversions of the inch sizes.
| Dimension | Millimetres | Inches |
|---|---|---|
| Cone bore d | 66.675 mm | 2.6250 in |
| Cup outside diameter D (3920) | 112.712 mm | 4.4375 in |
| Total width T | 30.162 mm | 1.1875 in |
| Cone width B | 30.048 mm | 1.1830 in |
| Cup width C | 23.812 mm | 0.9375 in |
Converted at 1 in = 25.4 mm and rounded to four decimals.
Mounting 3984 (general guidance)
General guidance, not a FULI specification: on a turning shaft the cone is a tight fit on the shaft and the cup a lighter fit in the housing, so the cup can be moved when the bearing pair is adjusted. Inch bearing fits are given as shaft and housing limits in inches in the bearing makers' tables; follow the drawing of your machine.
Tapered roller bearings carry radial load and axial load in one direction, so 3984 is normally used as one of a pair, and the end play or preload is set at mounting.
If the outer ring turns and the shaft stands still, as in an idler pulley or a wheel hub, the fits are reversed: the housing gets the interference fit (for example N7 or P7) and the shaft a sliding one (g6 or h6).
Grease for 3984
FULI supplies tapered roller bearings rust-protected and normally without grease; grease is packed in when the bearing is mounted. Relubricating 3984/3920 from the side takes about 17.0 g each time by the formula in our grease calculator: 0.005 × D × T = 0.005 × 112.71 × 30.16.
How FULI supplies 3984
3984 is supplied as a cone, as a cup or as a complete cone and cup pair, as your order states. Where an order states a requirement for the total width T (30.162 mm for 3984/3920), each set is checked on a height gauge before packing.
Rings are marked with a brand you are authorised to use, with the FULI brand, or left neutral, as your order states. The box is printed with the model, precision class and brand.
Inquiries that give only one number are the usual cause of a wrong quote, so write both the cone and the cup number, for example 3984/3920.
Tools and guides for 3984
Typical applications
- Vehicle wheel hubs and axles
- Gearboxes and reducers
- Agricultural machinery
- Conveyor pulleys
FAQ
What size is 3984 in mm?
The 3984 cone has a 66.675 mm bore (2.625 in). With cup 3920 the bearing is 66.675 × 112.712 × 30.162 mm (d × D × T).
What is the difference between 3984 and HM212049?
HM212049 has a 66.675 mm bore against 66.675 mm for 3984, and pairs with cup HM212011 (66.675 × 122.238 × 38.1 mm) instead of 3920 (66.675 × 112.712 × 30.162 mm). The two are not interchangeable; order by the numbers on the old cone and cup.
How much grease does 3984/3920 need?
About 17.0 g each time it is relubricated from the side (0.005 × 112.71 × 30.16). FULI ships it rust-protected without grease, so the first fill is made at mounting.
Which cup goes with the 3984 cone?
FULI's catalog pairs the 3984 cone with cup 3920. Tell us whether you need the cone, the cup or both when you send the inquiry.
Is 3984 the same size across brands?
3984 is an inch tapered roller bearing cone number. Most makers use the same cone and cup numbers for the same size, but check the cup number too. Send us the numbers on your old bearing and we confirm the match.