How Are Trailer Leaf Springs Weight Capacities Rated

Question

Question:

When a leaf spring is rated at 3500 lbs. is that 3500 per pair or for each spring?

asked by: Vic

0

Expert Reply:

There is usually two capacities listed on a leaf spring. The spring capacity and the axle capacity.

For the 4-Leaf Double-Eye Spring # e54SR that you referenced it has a spring capacity of 1,750 lbs meaning that the individual spring can handle 1,750 lbs. The axle capacity is 3,500 lbs meaning that when you use two springs the combined capacity is 3,500 lbs.

I attached an FAQ article on trailer suspension for you to check out also.

expert reply by: Jameson C

0

Danny

5/16/2025

Hi just to clarify the spring rating. Am building a 2000 kg total capacity trailer - tandem axle Will 4 x 500 kg single leaf springs be fine ?? They will prob be Rocker set up Regards D

Jameson C.

5/19/2025

@Danny Yes they would. That would add up to enough capacity.

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