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2-1/8 x 5-3/8" Square U Bolt Kit with Plates Trailer Boat Axles 1/2" 2 x 2 Tube (UBK-2000-SQ)

$43.89
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At a Glance

  • SKU: UBK-2000-SQ
PRODUCT INFORMATION

Product Details

R & P Carriages

2-1/8 x 5-3/8" Square U Bolt Kit with Plates Trailer Boat Axles 1/2" 2 x 2 Tube

Part Number: UBK-2000-SQ

Square u-bolt hardware kit for 2" x 2" square trailer or boat axle tube setups. Includes four square u-bolts, two tie plates, two spring perches, and eight nuts for a complete mounting hardware package.

R&P Knowledge Hub

What this kit supports: This kit is built around a 2" square axle tube with square-bend u-bolts and matching hardware for leaf spring mounting.

What the BOM confirms: The bill of materials shows 4 square u-bolts, 2 tie plates, 2 spring perches, and 8 nuts, so this is more than just loose u-bolts and nuts.

Measurement note: The updated product diagram now carries the dimension callouts directly. For this kit, 1/2" is the rod diameter, 2-1/8" is the width shown on the diagram, and 5-3/8" is the u-bolt length shown on the diagram. It should not be described as an internal length.

Before ordering: Verify 2" x 2" square tube axle size, hardware style, spring seat layout, and matching plate/perch requirements before installation.

R&P Service Insight

On square axle service work, it is important to think of the hardware as a clamping system. The u-bolts, plates, perches, and nuts all work together to keep the spring stack aligned and secured.

  • Correct Bend Style: Square-bend u-bolts should match the square axle tube profile
  • Complete Hardware Matters: Tie plates and perches are part of the system and should not be overlooked
  • Verify Threads and Fit: Check thread condition, perch center hole, and plate width before assembly

Features

  • Complete kit includes four square u-bolts, two tie plates, two spring perches, and eight nuts
  • Square u-bolts measure 2-1/8" width with 5-3/8" u-bolt length and 1/2" rod diameter
  • Designed around 2" x 2" square axle tube applications
  • Suitable for trailer and boat axle leaf spring hardware setups using square-bend u-bolts

Specifications

Specification Detail
Part Number UBK-2000-SQ
Product Type Square U-Bolt Kit with Plates and Spring Perches
U-Bolt Quantity 4
U-Bolt Bend Style Square Bend
U-Bolt Diameter 1/2 in
U-Bolt Thread 1/2"-13
U-Bolt Width 2-1/8 in
U-Bolt Length 5-3/8 in
Axle Tube Fit 2 in x 2 in square tube
Tie Plates Included 2
Spring Perches Included 2
Spring Perch Center Hole 0.625 in
Nuts Included 8
Application Trailer / boat axle leaf spring mounting hardware

Measurement Reference

Updated square u-bolt product diagram with dimensions

The product image is the measurement reference. The 5-3/8" callout is the u-bolt length shown on the diagram, not an internal length.

Measurement Description Value
Rod Diameter U-bolt rod thickness 1/2 in
Width Width shown on product diagram 2-1/8 in
U-Bolt Length Length shown on product diagram 5-3/8 in

Fitment / Application

Category Details
Axle Style 2" x 2" square axle tube
Suspension Type Leaf spring setup
Hardware Style Square-bend u-bolts with tie plates and spring perches
Important Notes Confirm axle dimensions, perch layout, spring stack height, and hardware compatibility before ordering or installation

Included Components

Quantity Item BOM Reference
4 Square u-bolts, 2.125" x 5.378" x 1/2"-13 32443
2 U-bolt tie plates 32491U
2 Spring perches for 2" square tube, 0.625" center hole SP-2
8 1/2"-13 u-bolt nuts UBN-8C

Verify axle tube size, spring perch requirements, and all hardware dimensions before installation.

UBK-2000-SQ, 2-1/8 x 5-3/8 square u bolt kit, 2 x 2 square tube u-bolt kit, trailer boat axle u-bolt kit, square u-bolt kit with plates, u-bolt kit with spring perches, 1/2 inch trailer axle u-bolts, 32443 32491U SP-2 UBN-8C

Related Parts & Kits

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815-357-3292  ·  270 E Jackson St  ·  Seneca, IL 61360

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Ordered trailer repair parts repeatedly; praised fast service, careful packing, and accurate orders.

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Found the correct RV keys at a good price with free shipping; the keys worked as expected.

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Needed an unusual axle and leaf-spring size; the team listened and helped him sort out the fit.

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