3-Leaf Double-Eye Spring for 2,000-lb Trailer Axles Shackle Bolt Diameter

Question:

What is the size of the center bolt in your leaf springs? I need to have a custom axle built to mate up with your springs SP-169275. I know the holes in the spring seat is 11/16, but I dont know the size of the bolt head or nut that will fit in that hole. These two dimensions are important regarding the tolerances of the axle length and spring center-to-center distance. I am completely rebuilding the tandem-axle carriage on which my trailer rides. Rails, shackles, equalizer, leaf springs, axles, hubs, brakes, the works. The total weight of boat, gear, fuel, and trailer is around 3,200 lbs, give or take. I have read that one should size axles and leaf springs so that one axle can support the full load. This is for going over bumps, crowns of launches, road construction, etc. This makes the choice easy: 3,500 lb axles and matching springs. However, with two of these axles and four of these springs, my suspension would be suited for a load over twice what I expect to tow. Im afraid Ill rattle my old boat apart on the highway. Going with two 2,000 lb axles and four 1,000 lb springs seems reasonable, but pushing it if I have to drive over a bump You have always offered great advice. I look forward to your answer

asked by: Kristofer D

Expert Reply:

The 3-Leaf Double-Eye Spring for 2,000-lb Trailer Axles - 20-3/8" Long part # e84SR takes a 9/16" diameter shackle bolt like part # 166081. The trailer's weight rating is determined by the two axle capacities so one axle would not need to be rated to support the whole load if it's a tandem axle trailer.

The capacities would be split up. If your boat is gear, fuel, and trailer is around 3,200 lbs I recommend to go with the 2-2,000 lb axles and 1,000 lb leaf springs because if not your suspension may cause a lot of bounce. As long as you do not exceed the two axle capacities you won't have any issues.

expert reply by: Heather A