TRAILER LEAF SPRINGS

HOW TO MEASURE WHEN REPLACING LEAF SPRINGS ON YOUR TRAILER.

Match the existing spring according to its shape and type (double eye, slipper-open eye end, slipper-hook end, slipper-flat end, or slipper-radius end). Count the number of leaves, each layer of spring metal is considered a leaf. Measure the length of the spring (see diagram below) when the spring is not under load, this is the free length of the spring. Be sure to measure from the center of the attaching eye in a straight line to the middle of the other eye or contact point, except Radius End which is measured from eye to end of spring.  The inside diameter of the bushing in the attaching eye of the spring, I. D. Bushing, needs to match the shackle bolts used to mount spring to hanger. 9/16" is the most common size, but some trailers use 1/2" bolts.  All our leaf springs are supplied with a 9/16" ID bushing in the closed eye, but this dimension can be changed by using different bushings. Also note that spring capacity is given per each spring-thus a 4,000 lb. rated axle should be matched with two 2,000 lb. or higher capacity springs.