How many lb of payload does a leaf spring add?

[BBBTree]

I have a 9 spring pack with an overload spring floating over the top of the pack. The truck is a class 3 rated for 14,000 lb.

If I add a spring to each side, what kind of payload capacity am I adding on to it?

 

[Tom Dunlap]

Be careful...I know where you're going.

The catch is that your truck may be built strong enough to haul the load but the factory rated it for a specific load. If you get caught with more load than your truck is rated for you can get yourself in some deep trouble...and tall fines. There are stories of over-loaded trucks being impounded then having to off-load and double haul the excess. After that's all done...pay fines, etc.

Look on the door column to find the chassis rating.

Any good spring shop will be able to help you setup your truck to maximize the carrying capacity.

 

[BBBTree]

I'm not thinking over loading the truck. I'm thinking over build the suspension by a few thousand lb capacity to keep from wearing out my springs so quickly again. I don't plan on buying new ones, so I'm concerned about them flattening back out sooner than what I would be okay with.

I'm either going to put on an extra leaf or two, or I'm going to put on the air bags. Either way, I'm having the flat ones re-arched tomorrow.

At this point after considering what you are pointing out I'm thinking a leaf or two will be plenty of payload bolstering, and I'll probably just skip the air bags.

 

[Treebobb]

I believe you said that your springs looked bent at the eyes. This is the overall weak point in leaves. The overload leaves on top help a lot and this is where you will add your strength but only to an extent. Airbag your truck. It directly transmits load from your axle to the chassis.

 

[BBBTree]

Funny thing is that the guy that re-arches refuses to sell or install air bags. He says he doesn't believe in them because they "rip, puncture, and tear out hoses....." We'll I could see fellas driving the 4x4 trucks through the sticks ripping up their rubber gear in the under carriage, but I can't imagine a service truck riding around the streets and highways doing that.

So I have to have the air bags installed somewhere else.

 

[Tom Dunlap]

Air bags aren't that hard to install. Keep a bicyle pump in the truck to top off the bags. I had them on my one ton cube van that I used for a service vehicle.

 

[BBBTree]

Bicycle pump is a good idea........if I get the bags. My spring guy is telling me I can get 1500 - 2000 lb by adding two extra springs to each side. That's all I need to prevent added wear and tear on the suspension. To re-arch and cut 4 new springs is $700. That's a little cheaper than re-arching and installing air bags. The truck goes in on Friday.

You must have a lot of trucks to keep up with, don't you Tom?

 

[BigWood]

[ QUOTE ]
Bicycle pump is a good idea........if I get the bags. My spring guy is telling me I can get 1500 - 2000 lb by adding two extra springs to each side. That's all I need to prevent added wear and tear on the suspension. To re-arch and cut 4 new springs is $700. That's a little cheaper than re-arching and installing air bags. The truck goes in on Friday.

You must have a lot of trucks to keep up with, don't you Tom?

[/ QUOTE ]

All well and good being able to carry more, but were the BRAKES built to STOP it!

 

[BBBTree]

That's a good point, but no way is their going to be 10,000+ lb sitting on the truck. I'm not going to put this old truck to the test.....or it's brakes.

 

[Tom Dunlap]

Over the years I was in the mode of having repair bills instead of new truck payments. It seemed to work for me since I could do a lot of the repair work for myself and still get treework done too.

During my business years I had some good friends who had mechanic backgrounds who would give me good advice. This is years before Internet was around so finding good advice and info wasn't as easy.

Right now, this is my fun mobile. The other one is a plain ol' '98 GMC Safari Man-ee van The ToyBox is going to become a camper.

 

[BBBTree]

Exactly. It's repair costs over payments, and I do almost all of my repairs.

That's good truck/camper. Do you have a bed in there? Any sink and table stuff?

 

[Tom Dunlap]

The bed is in...next I start on the galley and wiring.

 

[BBBTree]

That's great...especially when you can DIY.


Hey, I was talking to ladies at the scales at the dump today, and one was saying that I can add springs to my truck and, go to the DMV to pay to have the load limit raised. I'm going to check on that. I sort of doubt it. We already settled on that kind of thing being a bad idea.

I also found out that the fine here for overloading is $5 per lb.

 

[Tom Dunlap]

You can raise the load limit up to the factory rated load limit. All you're doing is paying the state more for wearing out the roads faster.

It's very unlikely, and expensive to have a chassis load rating changed.

 

[BBBTree]

The truck is done. It rides great; not so wobbly, tires aren't rubbing. It sits up about another 3-4 inches with the re-arch work and 2 new leaves installed on each side. One leaf was broken, and it looks like it's been broken for a long time.

$725 out the door.

 

[BBBTree]

The truck rides great with a load of wood in it now. It actually feels normal now. I can take turns without rubbing the tires on the bottom of the box deck.