Where to Measure to Pick Out Replacement Trailer Leaf Spring

Question:

I have a a-frame trailer thats 11 years old and the springs squeak like crazy. Id like to replace them. They are #3000 springs, but were put on a #3500 Dexter axle and the mfg tells me they put #3500 springs on all the later models. So, Id like to buy #1750 springs. The problem I have is measuring. Its hard to do your A to Ainch measurement because the axle is directly in they way. From the one static hanger bolt to the other static hanger bolt it about 25.25. The A to Ainch measurement seems longer, but the spring is also flattened out some and the shackle straps sit at a forward angle. So, should I just assume a 1724 would fit this? Or would be too short? Thanks!

asked by: Al

Expert Reply:

The absolute best way to measure your leaf springs is with them removed so that there is no weight on them which would cause them to flatten out. With the trailer frame jacked up you can get a pretty close approximation since you can remove the load, but in a situation where you can't get a decent measurement removing the spring would be ideal.

The # e57SR you referenced measures 25-1/4 inches long but the recommended hanger spacing is 24-7/8 inches since you want the shackle strap to angle out when installed.

Since your hanger spacing is 25-1/4 inches on center you would want a spring slightly longer. Based on you current dimensions the # e27SR which measures 26 inches long would be the best. But it is a 4,500 lb axle spring.

I would recommend trying to get a decent measurement of your leaf spring unloaded. Hopefully it's a tad bit longer than 25-1/4 inches so the # e57SR would work.

expert reply by: Jameson C