RALZAOTO Trailer Axle Bearing Kit 4-Set for 7000 lb D42 Spindles — 25580/14125A Bearings & Double-Lip Seals (10-36,10-10)

RALZAOTO 4 Sets 7000 LB Trailer Axle Bearing Kits supply complete spindle-to-hub hardware for tandem 7000 lb axles with D42 spindles, including bearings, races, double-lip grease seals, cotter pins and tang washers.

These complete bearing kits are designed to replace worn hub internals on trailers rated up to 7,000 pounds per axle with a #D42 spindle. Each kit set combines matched bearing cones and races (25580 / 25520 and 14125A / 14276), plus robust double-lip grease seals in two common sizes for D42 spindles and all required small hardware. The parts are manufactured for long life, quiet rotation, and improved hub sealing against contamination and grease loss.

Which trailer axles and spindles are these kits compatible with?

This kit targets tandem and single axles rated around 7000 lb that use the D42 spindle profile. Confirm compatibility by matching your spindle ID and bearing numbers on your current hub before ordering.

• Fits 1.25" to 1.75" spindle diameter ranges typical for 7000 lb axles.
• Includes bearings 25580 / 25520 and 14125A / 14276 for common hub combinations.
• Contains two grease seal sizes for D42 spindle variations: 10-36 and 10-10.

How does the double-lip grease seal improve hub reliability?

The double-lip seal design creates two sealing edges to keep grease in and dirt and water out of the hub cavity. This reduces the risk of bearing contamination and premature wear, especially in wet or sandy conditions like boating or off-road towing.

• Two sealing lips for enhanced protection against moisture and road grime.
• Durable elastomer construction to maintain a tight fit under centrifugal force.
• Minimizes grease loss and lowers maintenance frequency for trailers.

What parts are included and how many pieces come with the 4-set pack?

The 4-set package supplies everything needed to service two tandem axles or four wheel hubs on a single tandem axle trailer. Parts are supplied in matched groups to ensure correct fit and balanced hub operation.

• 4 bearing cones 25580 and 4 matching races 25520.
• 4 bearing cones 14125A and 4 matching races 14276.
• 4 double-lip grease seals sized 10-36 and 4 sized 10-10 for D42 spindles.
• 4 cotter pins and 4 tang washers to secure the castle nuts.

How will installing this kit affect trailer performance?

Replacing old bearings and seals with matched, precision parts restores hub concentricity and reduces friction, which helps hubs spin smoothly and quietly. Properly serviced hubs also lower heat build-up during towing and reduce the chance of sudden failures on the road.

• Restores correct bearing preload and hub alignment for stable towing.
• Reduces operational noise and rolling resistance at highway speeds.
• Improves seal integrity to protect bearings from contaminants and water.

Who is this for: These RALZAOTO kits are aimed at trailer owners, fleet maintenance teams, and DIY mechanics who maintain boat trailers, utility trailers, RVs, or equipment haulers using 7000 lb axles with D42 spindles. If you need matched bearings, races, seals and hardware to complete a hub rebuild for one or more tandem axles, this 4-set package provides the components and seal options commonly required for reliable, long-term service. For best results verify bearing numbers and spindle size before purchase, and follow torque and packing guidelines when installing.