Spring Pins

What is a leaf spring pin?

A spring pin is the pivot and attachment point used on many leaf spring suspensions using brass bushings. The spring pin will be made of hardened steel, and it may be smooth sided or threaded. Spring pins will be drilled and tapped for grease zircs and may have channels in the body to more effectively deliver grease to the spring bushings. Leaf spring pins may have notches cut into them where bolts are used to lock them into place and keep them centered.

Measuring Leaf spring pins for replacement and identification

When replacing leaf spring pins, it is important to measure your old pins correctly to ensure a matching replacement can be ordered. Below you will find the information you should obtain before looking for replacement pins:

• Vehicle application – Knowing the application will be necessary for threaded pins as there are no normal means of identifying the thread size and pitch used. The threads for threaded spring pins exceed what will normally be found on typical thread gauges for size and thread pitch. The application can also help narrow down pins that may be similar in dimension.
• Pin diameter – Measure the diameter of the body of the pin where it will contact the spring bushing. If the pin in severely worn, it may be necessary to use information from the lead spring to order replacement pins. If the diameter of the pin changes on one or both ends also note that dimension.
• Pin length – Measure the total length of the pin from end to end.
• Distance between locking notches – If the pin had locking notched cut into it measure the center to center distance between the two. If only one notch is used, measure the distance between the center of the notch and the closest end of the pin.
• Locking mechanism type – Spring pins with lock notches will use bolts, square keepers, or cotter pins. Identify the type used on your suspension setup and take note.
• Grease zirc locations – Due to limited access some spring pins may have more than one grease zirc or multiple threaded holes for grease zircs. This will be important to ensure you can service the spring pin after the installation is done.