Replacement Slipper Spring for a Jon Boat Trailer

Question:

this trailer is about a 1978? I believe the axle weight is 500 lb but how can I be sure? and if I put bigger leaf springs as long as I do each side would it be ok. Its a boat trailer jon boat and I doubt what it weighs over 500lb with motor.

asked by: Dorin J

Expert Reply:

When replacing trailer leaf springs you are correct in that you want to do both sides at the same time. You can go a little over in capacity but if you go too much the suspension basically wouldn't function as it would be too stiff to move and absorb bumps.

When picking out a slipper spring the most important dimension you need to get from your old springs is the length of the spring when measured from the center of the bolt hole to the other end of the spring.

The 2-Leaf Slipper Spring # e29SR that you referenced has 30-1/4 inches for this dimension. If the spring you are looking to replace is that dimension or slightly longer when unloaded this would fit your trailer.

Since most likely you need a lighter rated slipper spring check out the part # SP-177275. This slipper spring is rated for 1,000 lb axles and has a length of 24-1/4 inches. Capacity-wise I think this would be the closest slipper spring to what you would need.

If your axle diameter is around 1-1/2 inches most likely its a 1,000 lb axle.

If you have a different length slipper spring or have any other questions email me back and I'll help you further.