Shackle Plates and Bolts

Shackle plates and bolts are vital components, often made from galvanised or high-tensile steel, used in trailer and caravan suspension systems to provide secure articulation between leaf springs and the chassis.

Shackle Plates

Shackle plates are typically sold as single items or as part of a kit and come in various dimensions to suit different spring widths and bolt sizes.

Material: Made from heavy-duty galvanised steel for strength and corrosion resistance.

Compatibility: Designed for eye-to-eye leaf spring suspension setups, with 65mm hole centres and 9/16″ diameter holes (approx. 14.3mm).

Installation: According to the Towing Project, they feature a direct bolt-on design for easy installation using standard spring hardware.

Shackle Bolts

Shackle bolts are specifically designed to fit shackle plates and spring eyes, often made from high-tensile steel and available in both greasable and non-greasable options.

Material: Made from high-tensile steel for durability.

Features: Includes a grease nipple for lubrication, is designed for use with steel bushes (not nylon), and comes with a Nyloc nut for a secure fit.

Installation: The bolt has a knurl that fits tightly into the shackle plate to prevent it from spinning, which can cause premature wear.

Components: This kit contains 2 x 16mm high-tensile shackle bolts and 2 x 32mm-wide shackle plates with 63mm centres.

Features: The bolt heads are welded into the shackle plate to prevent them from turning, a common practice to avoid wear and failure. The gold-coloured plating (SA5 ElectroGal) offers high resistance to saltwater and corrosive environments.

Key Considerations
Working Load Limit (WLL): Always ensure the WLL of the shackle plate and bolt matches or exceeds the requirements of your application. The WLL is the only rating you should pay attention to, with the minimum ultimate strength being around 6 times the WLL.

Material and Finish: Common materials include galvanised steel for general corrosion resistance and stainless steel for marine use. High-tensile steel is used for the bolts’ strength.

Compatibility: Ensure the hole spacing and bolt diameter of the plates match your leaf springs and the intended bolts (e.g., 65mm centre to centre for a 9/16″ bolt)

Maintenance: Regularly inspect shackle pins and plates for wear, rust, or elongated holes. Do not use a shackle if it is worn by more than 10% of its original diameter.