Leaf Spring Life

Is there a life expectancy for leaf springs? My 17 ft bassboat and equip probably weigh in at around 2000lbs max.. The Spartan trailer it sets on is just the 3500lb single axle with 13in wheels and tires. The rig is 1978 going on 35 yrs now. It really does not have a ton of road use miles as I've hauled mostly local over those years. I honestly cannot recall how the springs appeared when they were new. I've just noted the springs look pretty flat without much of an arch to them. I've noticed the trailer seems to ride pretty hard over bumps or rr tracks but as I mention, I'm never out on too many long hauls. I'm curious if there is a normal life expectancy where the load is just continually setting on a trailer for that many years. Thanks in advance.

Re: Leaf Spring Life

Springs do suffer fatigue and lose their set. As long as there is some spring in them and the axle isn't bottoming usually not an problem.

Re: Leaf Spring Life

I've just noted the springs look pretty flat without much of an arch to them

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I've noticed the trailer seems to ride pretty hard over bumps or rr tracks

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I am by far not a authority on springs, but from the things you have mentioned it would prompt me to have the rig weighed first. It could be from the boat weight, gear load and even water soaked foam. I would concider it a symptom and dig a bit deeper. Thier there to help prevent damage to the boat. Springs do lose thier temper over time and use but thier so many factors that come into play. But I have owned 1968 boats and trailers with original springs.

Re: Leaf Spring Life

I'm curious if there is a normal life expectancy where the load is just continually setting on a trailer for that many years.

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Nope,.... Not really....

It's a piece of steel,...
It either rusts away, get's broken, or bent....
Other than that, it'll sit there forever...

Got a Picture,..?? of the arch,..??

Re: Leaf Spring Life

Look at the spring shackles. The lower end of the shackle should have a slight rearward slant to them. If the springs have flattened, the shackle will have a radical slant to it and in fact may nearly touch the trailer frame. Stop by your local marina or boat dealer and look at a new(er) leaf sprung trailer. You will see what is normal.

Re: Leaf Spring Life

Shape can be different for different springs designed to carry different loads and whether it is a thin blade requiring 7 leafs to carry a certain load, or one of the thicker ones that only require 3 to carry the same load. I agree with silvertip on looking at the shackle at the rear. If yours are flat, might check closely at the center of the spring, where the pin goes that keeps them all aligned and look for a hairline crack running vertically across a leaf....that one is broken and may be your problem.

Most flat springs I have seen were on large, heavy equipment like a 37' rock bucket dump trailer, garbage truck, for a couple. Most boat trailer springs do have a set (deliberate curvature). They are specially heat treated steel....was in a spring shop in Dallas one time and saw them custom make springs for things like I mentioned. While there I had an additional leaf put in my 71 Chev station wagon to help in carrying the extra load when we went fishing for a weekend. Course some don't have a rear shackle; elcheapo that just have a sliding rear bracket and bang every time you hit a chug hole. With that one it's hard to tell. If it's functioning properly your boat shouldn't bottom out or ride hard whatever it is.

Mark