40mm Square Spring U-Bolt Kits – Galvanised

40mm Square Spring U-Bolt Kits | Hot-Dip Galvanised

The Couplemate™ 40mm u-bolt kit for square axles includes Galvanised u-bolts, nylock nuts, and fish plates.

Spring U-Bolt Kits are designed to secure leaf springs to trailer and caravan axles safely. U-bolts link your trailer and the road; hence, it is important to use u-bolts made from high-quality materials. 

Need new springs? See our range of leaf springs.

This U-Bolt Kit is supplied with:

• 4 x U-Bolts (choose preferred length)
• 8 x Washers
• 8 x Nyloc nuts
• 2 x Fish Plates
• 2 x Axle Pads/Spacers

40mm Square U-Bolt Specifications

U-Bolts are measured on their internal dimensions to ensure proper fit and alignment with the equipment. See our technical diagram for a visual reference.

• Internal U-Bolt Width: 40mm
• Internal U-Bolt Leg Length:
  • 100mm (4″)
  • 115mm (4.5″)
  • 125mm (5″)
  • 140mm (5.5″)
  • 150mm (6″)
• Thread: 1/2″ UNF (12.7mm)
• Coating: Traditional hot-dipped galvanised

Couplemate™️ supplies these 45mm square u-bolt kits for leaf spring suspension systems.

Installation (User Guide)

Couplemate™️ 40mm Square U-Bolt Kits are easy for trailer spring maintenance.

• Place U-shaped curve over axle beam.
• Align the centre spring bolt and U-bolt legs with the fish plate holes.
• Secure fish plate to leaf spring through supplied washers and nylock nuts. Tighten nuts to 60Nm with a socket.

Important: Check U-bolts and re-tighten nuts after the first trip and every 250 km thereafter.

Safety Precautions

• Do not re-use nyloc nuts. Nyloc nuts are often less effective after the first use. This is because the nylon material (the key component of a nyloc nut) has already once conformed to the thread profile. 
• Do not use a rattle gun to tighten. Rattle guns often tighten u-bolts too fast, too tight, and uneven. This can cause nylon overheat and risks undue wear. 
• Ensure the axle has welded axle pads. If not, use the axle pads supplied with the spring U-bolt kit.

See the range of other trailer and towing safety parts.

Available U Bolt Kits

• • 39mm Round Spring U-Bolt Kits – Galvanised
  • 40mm Square Spring U-Bolt Kits – Galvanised
  • 45mm Round Spring U-Bolt Kits – Galvanised
  • 45mm Square Spring U-Bolt Kits – Galvanised
  • 50mm Round Spring U-Bolt Kits – Galvanised
  • 50mm Square Spring U-Bolt Kits – Galvanised

• Heavy-Duty 45mm Square Spring U-Bolt Kit
• Heavy-Duty 60mm Round Spring U-Bolt Kit
• Heavy-Duty 65mm Round Spring U-Bolt Kit