iBroPrat Boat Trailer Bearing Kit for D42 Spindles — 4-Set 5,200–6,000 lb with 25580/15123 Bearings

iBroPrat 4Sets 5200–6000 lb boat trailer axle bearing kit is a complete 36-piece replacement set engineered to fit D42 spindles using 25580 and 15123 bearings.

This kit supplies everything needed to service four hubs on tandem axles rated 5,200–6,000 pounds. It consolidates inner and outer bearings, two common grease-seal sizes, spindle hardware, dust caps, cotter pins and protective plugs into one boxed package, saving trips to multiple suppliers and reducing per-unit cost compared with buying parts separately.

What parts are included and why does each matter?

The kit contains 36 components sized to work with D42 spindles and the specified bearing numbers. Each part complements the others so you replace a full hub assembly without hunting down mismatched pieces.

• 4× outer bearings (25580/25520) and 4× inner bearings (15123/15245) for proper load support.
• 4× 2.125" ID seals (21333TB/10-10) and 4× 2.25" ID seals (22333TB/10-36) to match common shaft diameters.
• 4× spindle nuts, washers, cotter pins, dust caps (2.44" OD) and rubber plugs for complete reassembly.
• All parts packaged as four full sets so you can service each hub on a tandem axle pair.

How do I confirm this kit fits my trailer spindle?

Measure your spindle and check existing bearing codes before purchasing. This set is designed for 1.25" to 1.75" tandem axles on D42 spindles that use bearing numbers 25580 (outer) and 15123 (inner).

• Verify your current bearing stamps read 25580/25520 and 15123/15245.
• Confirm spindle type is D42 and rated for 5,200–6,000 lb tandem axles.
• Check dust cap outer diameter of about 2.44" to ensure proper fit in hub recess.

What seal options are included and why two sizes?

The kit includes both 2.125" and 2.25" ID grease seals so you can match the shaft diameter without swapping kits. The double-lip seal design improves grease retention and helps keep contaminants out of bearings under wet and salty conditions common to boating.

• 21333TB/10-10 — 2.125" ID × 3.376" OD seals for smaller shafts.
• 22333TB/10-36 — 2.250" ID × 3.376" OD seals for slightly larger shafts.
• Double-lip construction on seals minimizes leakage and keeps grease where bearings need it.

How durable and serviceable are the components?

Components are made to withstand frequent marine use with precision-manufactured bearings and resilient seals. The kit aims for long service life and quieter operation when installed and greased correctly.

• Precision bearings reduce friction and operational noise under load.
• Grease seals with double-lip design improve longevity and prevent contamination.
• Parts are packed in heavy-duty box with bubble wrap to avoid shipping damage.

Who is this for: This iBroPrat kit is intended for boat owners, trailer service shops and DIY mechanics who maintain tandem-axle trailers rated 5,200–6,000 lb and who need a cost-effective, complete replacement set that matches D42 spindles using 25580 and 15123 bearings. If you prefer to replace all four hub assemblies at once, want both common seal sizes included, and value neatly packaged parts for straightforward installation, this kit is a practical choice.