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7,000 lb Build-Your-Own Trailer Axle Kit w/ 8 x 6.5 Lug Idler Hubs and #42 Square Spindle (BYOAK-42-H865-SQ)

$285.18
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Build-Your-Own Axle Series

7,000 lb Build-Your-Own Trailer Axle Kit w/ 8 x 6.5 Lug Idler Hubs and #42 Square Spindle

8-Lug Idler Hubs with #42 Square Weld-On Spindles. This KIT includes: (2) #42 square-base spindles
(2) 8-lug idler hubs – 8 on 6.5"
(2) Inner bearings – 25580
(2) Outer bearings – 14125A
(2) Grease seals – 10-10
(2) Grease seals – 10-36
(2) Dust caps – 2.71"
(2) Castle nuts
(2) Spindle washers
(2) Cotter pins and (16) Lug Nuts

SKU: BYOAK-42-H865-SQ 7,000 lb Capacity 8 on 6.5" Bolt Pattern
7,000 lb Axle Capacity
8 on 6.5" Bolt Pattern
Idler Hub Type
#42 Square Spindle Style

Key Measurements & Specs

SKU BYOAK-42-H865-SQ
Capacity 7,000 lb
Hub Type Idler (No brakes)
Bolt Pattern 8 on 6.5"
Spindle Base 2" square solid shaft

Fitment / Application

Application Straight axle fabrication
Spindle #42 square weld-on
Lubrication Standard, non-EZ-Lube
Axle Tube Not included
Fitment Check Verify all dimensions before fabrication

Top Features

Complete Pair Components for both axle sides
8-Lug Setup Two 8 on 6.5" idler hubs
Square Spindles Two weld-on #42 spindles
Bearing Hardware Kits, washers, nuts, and pins
Fabricator Format Select the axle tube for the build

Overview

This 7,000 lb build-your-own trailer axle kit is designed for fabricators and trailer builders who need an idler axle setup using 8-lug hubs and #42 square weld-on spindles.

The kit provides the hub, bearing, seal, dust-cap, spindle, washer, castle-nut, and cotter-pin components needed to fabricate a straight axle. The axle tube is not included.

R&P Service Insight

A fabrication-focused axle package

This kit is intended for builders who need the spindle, hub, bearing, seal, and retaining hardware while supplying the axle tube separately. Confirm the required hub-face dimension, spring-center dimension, tube size, and finished axle capacity before beginning fabrication.

R&P Knowledge Hub

What “build your own axle” means

The spindle placement and axle-tube length establish the finished hub-face measurement. Because the axle tube is not included, the builder is responsible for selecting the tube and establishing the final axle geometry for the intended trailer application.


Brand & Fitment Note

Match the listed 7,000 lb capacity, 8 on 6.5" bolt pattern, bearing sizes, seal sizes, and #42 spindle dimensions to the intended build. This is a fabrication kit and is not a preassembled axle.

R&P Repair Insight

Alignment determines the finished axle

Both spindles must be positioned and aligned correctly before final welding. Improper alignment can affect tire wear, tracking, bearing life, and overall trailer performance. Fabrication should be completed by a qualified technician.

Features

01 / CAPACITY

7,000 lb Axle Setup

Components are configured for a 7,000 lb build-your-own idler axle application.

02 / HUBS

8-Lug Idler Hubs

Includes two idler hubs with an 8 on 6.5" wheel bolt pattern.

03 / SPINDLES

#42 Square Spindles

Includes two weld-on spindles with 2" square solid-shaft bases.

04 / BEARINGS

Bearing Kits Included

Two bearing kits supply bearings, grease seals, and dust caps for both hubs.

05 / HARDWARE

Spindle Hardware

Round spindle washers, castle nuts, and cotter pins are included.

06 / FABRICATION

Builder-Selected Axle Tube

The axle tube is supplied separately so the builder can establish the required finished dimensions.

Included Components

Quantity Part Number Included Component
2 SP-50642-SQ #42 square weld-on spindles
2 82865-1 8-lug idler hubs with 8 on 6.5" bolt pattern
2 HD-7000-KIT 7,000 lb bearing kits with dust caps
2 SW1000 Round spindle washers
2 FA-SN100 Castle nuts
2 165649 

Cotter pins 

Bearing Kit Breakdown

Quantity Per Kit Part Number Component Measurement
1 021-043-02 Dust cap 2.71" OD
1 25580 Inner bearing 1.75" ID
1 14125A Outer bearing 1.25" ID
1 10-10 Grease seal 2.125" ID
1 10-36 Grease seal 2.25" ID

Quantities shown are for one HD-7000-KIT bearing kit. This axle kit includes two bearing kits.

Specifications

Specification Detail
Part Number BYOAK-42-H865-SQ
Product Type Build-your-own idler axle kit
Axle Capacity 7,000 lb
Hub Type Idler
Bolt Pattern 8 on 6.5"
Spindle Type #42 square weld-on
Weld-On Base 2" square solid shaft
Grease Type Standard, non-EZ-Lube
Axle Tube Not included

Spindle Details & Dimensional Chart

SP-50642-SQ number 42 square weld-on trailer spindle dimensional chart

SP-50642-SQ #42 square weld-on spindle dimensional reference

11" Overall Length
2" Square Solid Weld-On Base
1" Top Journal Diameter
5.93" Shaft Length

Not Included

  • Axle tube — typically 3" or 4" square tubing depending on the application
  • Brake components
  • Wheels or tires

Important Installation Note

This kit is intended for fabrication use. Welding, spindle alignment, axle-tube selection, and final installation should be completed by a qualified technician. Always verify dimensions, component compatibility, and load requirements before fabrication or installation.

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Trailer Parts Knowledge • Product Support • NeedATrailerPart.com

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