66-400F-NS – 8,000 lb Drop Spindle – 4" Drop – Weld-On – EZ Lube
Part Number: 66-400F-NS
Heavy-duty MAT weld-on drop spindle designed for 7,000 lb to 8,000 lb trailer axles. Features a 4" drop configuration, integrated EZ Lube grease zerk, and pre-welded heavy-duty 4-bolt brake flange. Ideal for replacing damaged axle ends or fabricating custom drop axle assemblies.
This spindle is commonly used on Lippert-style 8K axles and is compatible with many TruRyde-style 8K hub and brake assemblies when bearing and brake specifications match.
Features
- MAT manufactured heavy-duty weld-on spindle
- Rated 4,000 lb per spindle (8,000 lb per axle)
- 4" drop lowers hub centerline without axle flip
- Integrated EZ Lube grease zerk fitting
- Pre-welded 4-bolt heavy-duty brake flange
- Designed for 3.5" round axle tubes
Specifications
| Capacity | 4,000 lb per Spindle (8,000 lb per Axle) |
| Drop | 4 Inches |
| Axle Tube Fitment | 3.5" Round Tube |
| Brake Flange | 4-Bolt Heavy-Duty Flange |
| Brake Compatibility | 12-1/4" x 3-3/8" Electric or Hydraulic Brakes |
| Hub Compatibility | Common 8-Lug (8 on 6.5") Hub & Drum Assemblies |
| Inner Bearing | 25580 |
| Outer Bearing | 14125A |
| Type | EZ Lube (Grease Zerk Installed) |
| Weight | 17.25 lbs |
Fitment & Common Applications
- Replacement for bent or damaged 7K–8K spindles
- Custom fabricated 8K drop axle builds
- Leaf spring trailer suspension systems
- Compatible with many Lippert-style 8K axle configurations
- Commonly used with TruRyde-compatible 8K hubs when bearing specs match
Professional welding required. Confirm bearing journal dimensions, brake flange bolt pattern, axle tube diameter, and hub compatibility before installation.