I just broke both main leafs on my car trailer on one side. It has 3 leaf springs which I like because they have a little give unlike the 4 leaf springs that ride like a brick. They both broke on the shackle side near the U bolt plate which is not rounded away from the spring like on some trailers I have seen. I have broke the springs on my bike trailer (3500 lb axle with 10" brakes) numerous times also before switching it to Jeep Wrangler springs. My buddy whom used to work at Family RV says he sees trailer springs all the time. Are trailer springs made cheap and prone to breakage or do I need a heavier spring? I see that my springs according to the Northern Tool site only lists them as 6000 lb or so but they have supported maybe 9000lbs and more (truck, spares and trailer) several times including several trips hauling a Class 8 truck to Baja. What springs do you have and have you had any problems with the 3 leaf lighter springs. Buy the way I looked at my buddies 6 leaf trailer springs and they are too soft for my taste so I guess the rates can vary considerably depending upon thickness and taper of stack etc.