FK FKSSX5T Spherical Bearing – 5/16? Bore, Precision Narrow Series
Genuine FK Rod Ends FKSSX5T high-performance spherical bearing — a 5/16" (0.3125") bore, all-stainless, PTFE-lined precision narrow-series bearing built for the demands of motorsport suspension, steering, and chassis pivots. The FKSSX-T series is one of the most widely used race bearing families in the world, and the -5 size is a staple in Formula Ford, Formula 2000, sprint cars, and countless custom chassis, especially used in shock damper bolt locations.
Press this bearing into a housing, tube, or bracket to create a high-strength, self-lubricating pivot with a full 12° of misalignment — ideal wherever a rod end won’t fit but you still need articulation under high load.
All-Stainless, Self-Lubricating Construction
- Ball: 400 series stainless steel, heat treated, for strength and corrosion resistance. A little bit stronger and robust option would be the Aurora PNB-5T bearing, as it has a Alloy steel – heat treated – hard chrome plated ball.
- Race: 17-4 PH stainless steel, heat treated
- Liner: PTFE liner standard — self-lubricating, maintenance-free, quiet, and resistant to loosening between ball and race
- Precision: B and D diameters concentric within .005 TIR for accurate press fit and true running
- Optional staking groove available (suffix “TV”, e.g. FKSSX5TV) to positively retain the bearing in its housing — contact us if you need the TV version
Specifications (FKSSX5T)
| Manufacturer | FK Rod Ends |
| Part Number | FKSSX5T |
| Series | FKSSX-T Precision Narrow Series |
| Bore (B Dia) | 5/16" — 0.3125" (+.0000 / -.0005) |
| Outside Diameter (D) | 0.7500" (+.0000 / -.0005) |
| Ball Width (W) | 0.375" |
| Race Width (T) | 0.281" |
| Ball Diameter | 0.562" |
| Misalignment Angle | 12° min |
| Ultimate Radial Load | 10,400 lbs |
| Radial Static Limit Load | 8,750 lbs |
| Axial Static Limit Load | 700 lbs |
| Oscillating Load Rating (PTFE) | 5,460 lbs |
| Approx. Weight | 0.03 lb |
| Sold As | Each |
Cross-Reference / Compatible Bearings
The FKSSX5T is dimensionally interchangeable with other manufacturers’ 5/16" bore precision narrow spherical bearings of the same series. Compatible / equivalent part numbers include:
- Aurora PNB-5T (Aurora Bearing / Timken) — the direct equivalent: 5/16" bore, 0.750" OD, 17-4 PH stainless race, PTFE lined
- Aurora PNB-5TG — Aurora’s staking-groove version (cross-references to FK’s FKSSX5TV)
Cross-references are provided for dimensional interchange. Load ratings, liner specification, and misalignment may vary between manufacturers — verify the spec critical to your application. If your chassis manual calls out the Aurora PNB-5T, the FK FKSSX5T is the accepted equivalent, and vice versa.
Applications
- Suspension pivots, bell cranks, and rockers
- Steering and linkage joints where a pressed-in bearing is preferred over a rod end
- Formula Ford, Formula 2000, sprint car, and custom chassis pickups
- Any 5/16" bore housing needing a high-load, self-lubricating articulating joint
- Ligier JS F3 car uses them in the shock dampers
