Description
Aluminum 6-hole oil/grease hub cap with rubber side plug and replacement gasket for trailer and tractor steer/drive wheel ends. The Power Products 84009B fits the industry-standard 4009 6-on-5-1/2″ bolt pattern (5/16″ bolt size) used on a wide range of medium- and heavy-duty trailer hubs, and is a direct fit replacement for Stemco 343-4009 / 340-4009 / 300-4009 / 352-4009 wheel-end caps.
Signs You Need a New Hubcap
- Cracked, dented, or deformed cap allowing oil or grease leaks at the wheel end
- Missing or hardened side fill plug
- Damaged or compressed gasket causing seepage at the bolt flange
- Cap removed for bearing service and not reinstalled with a fresh gasket
Specifications
| Manufacturer | Power Products |
|---|---|
| Part Number | 84009B |
| Part Type | Wheel Hub Cap with Side Plug & Gasket |
| Bolt Pattern | 6-hole, 5-1/2″ bolt circle |
| Bolt Size | 5/16″ |
| Material | Aluminum cap; rubber side plug; replacement gasket included |
| Cap Style | 4009 pattern (oil/grease, side fill) |
Cross References
This hub cap replaces or is equivalent to the following part numbers:
- Stemco: 343-4009, 340-4009, 300-4009, 352-4009
- Also known as: 4009 (industry pattern designation)
Applications
This hub cap fits 6-on-5-1/2″ wheel-end hub flanges commonly used on:
- Medium- and heavy-duty trailer axles with 22.5K–27.5K capacity hubs
- Dexter and similar trailer-axle hubs accepting the 4009 6-bolt pattern
- Replacement on existing wheel ends running Stemco 300-4009 / 343-4009 / 340-4009 caps
Verify the bolt pattern and bolt circle on your existing hub before ordering. Always replace the gasket when removing or installing a hub cap.









