Recommended Leaf Spring Capacity for a Conversion Boat Trailer

Updated 04/10/2018 | Published 04/07/2018

Question:

I have an older boat trailer with, what I believe to be, leaf springs that are probably around 1000 lb capacity each. I believe its a 2000 lb axle. I am setting it up to be a kayak trailer and the typical load will be 160-200 lbs and will probably never exceed 350 lbs with 2 kaysks. Assuming the trailer frame itself is 150 lbs, would it be acceptable and be a better ride on the equipment to install lighter leaf springs say 300 lb capacity x 2 in leu of the 2000 total capacity springs? Or am I totally misunderstanding the concept of the suspension?

asked by: Kevin

Expert Reply:

Yes and no, a leaf spring with a lower capacity will provide a better quality ride than a leaf spring with a higher capacity but you will not want to make that part the lowest rated suspension component. Typically, we recommend choosing a leaf spring with a capacity that either meets or exceeds the capacity of the axle. I would be skeptical if the leaf spring pack you have now is only rated at 1,000 lbs.

However, since you have converted a boat trailer to a light duty kayak carrier I suppose it would be okay to choose a leaf spring with a capacity lower than than the axle capacity but I would not go as low as 300 lbs. For your application, I would stick to a set of leaf springs rated around 1,000 lbs -1,500 lbs. Using a 300 lb leaf spring on this trailer would be very bouncy and unsafe.

In order to recommend the correct leaf springs for your trailer, I would need to know the style (slipper/double eye) in addition to the overall length/width. Please keep in mind that over time as springs wear out they will tend to be a bit longer than when originally installed. I have attached our leaf spring selection for you as well.

expert reply by: Conner L