Replacement Boat Trailer Leaf Spring Due to Age and Corrosion of Salt Water

Question:

My boat trailer is aluminum and has eye to eye leaf springs that are 23inch center to center. The old springs are in really rusty and are in bad shape and need to be replaced. I have not seen any galvanizedinch leaf springs. I cannot tell if the originals were galvanized because they are quite old. My instincts are that they are not. The constant friction would likely defeat any advantage to being galvanized since it would wear through the galvanized exterior fairly quickly. But I just wanted to be sure before making the purchase since this trailer is in and out of salt water a lot. Thanks in advance for your response.

asked by: Joe U

Expert Reply:

I personally have never seen any galvanized or other coatings put onto leaf springs. I agree with you that whatever coating that may be put on them would surely wear or peel over time.

The most important thing with replacing leaf springs is getting the correct spring. For this you will want to know the the specifications of your trailer as well as what springs you had. I have included a picture to help with the measurements.

Weight Rating of Axle and Trailer
Number of Spring Leaves
Eye to Eye Measurement (A)
Length from Eye Center to Spring Pin (B)
Height from Eye Center to Spring Pin (C)

Older springs would have shown some sag so the height and eye to eye measurements may be slightly different.

The 3-Leaf Double-Eye Spring # e59SR has an eye to eye of 23-1/8"(A), Length of eye to pin is 11-9/16"(B) and Height of 3-1/2"(C). This spring is rated to be used on a 3,500lb axle and is constructed of 3 leaves.

An easy rust preventative product you could try is WD-40 on the springs. It is a Water Displacement product that is was designed to protect bare steel.