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Discussion Starter #1
I think I have the off road package and I'm thinking about removing a leaf. I'm sure as you guys know, it rides like an empty dump truck. It doesn't take a whole lot of weight to make it ride so much better. Being this is my DD, it'd be nice to make the ride nicer.

A few months ago, I had 2 tons of broken concrete in the back. The truck sat level....maybe 1" lower in the rear. This tells me I really have way more spring than I need. Trailers that I pull only weigh 6000# or so.

How much payload will I lose? How about ride height? Which spring should I remove?

Thanks guys,
Steve
 

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I think I have the off road package and I'm thinking about removing a leaf. I'm sure as you guys know, it rides like an empty dump truck. It doesn't take a whole lot of weight to make it ride so much better. Being this is my DD, it'd be nice to make the ride nicer.

A few months ago, I had 2 tons of broken concrete in the back. The truck sat level....maybe 1" lower in the rear. This tells me I really have way more spring than I need. Trailers that I pull only weigh 6000# or so.

How much payload will I lose? How about ride height? Which spring should I remove?

Thanks guys,
Steve
I've been looking at this for a while now. I have a thread in the towing and hauling section if you want to read it.

From the research that I have done, it seems as though the removal of any leaves will lead to major axle wrap. Even stock, the leaves have a hard time holding it.

My summer project will be to remove all but two or three leaves, install a set of airbags to regain the lost payload capacity and install a set of traction or ladder bars.

I'm hoping this will also help out with the bed hop that I get.
 

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What lonestar has listed is really the only safe way to do it. If you are going to remove anything you want to add the traction bars to control wrap, and if you use your truck at all with any sort of weight in the back you will want to put the air bags under there. You can keep them at about 20psi when not needed for the nice ride, but they are always there when you need your truck to be a truck.
 

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A leaf spring is designed so that each leaf sustains an equal amount of bending stress.
http://www.me.mtu.edu/~mavable/Book/Chap7.pdf
diagram, bottom of p.333

Removing one leaf will create a stress concentration in the leaf above the one removed, which often results in a broken leaf, which leads to an even bigger stress concentration in the next leaf up, et cetera.

The best way is to replace the entire spring with one that's not as stiff. If you insist on removing one leaf, calculating the remaining spring rate and capacity is pretty elementary. Given the actual dimensions of each leaf, any mechanical engineering sophomore should be able.

Axle wrap is pretty much an imaginary "problem" for anybody except drag racers. It doesn't happen in normal driving unless you're driving like a knucklehead, in which case the solution doesn't include adding racing hardware to an on-highway vehicle.
 

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Discussion Starter #5
Well, I actually have some inexpensive traction bars in the garage waiting to be installed. I actually do have axle wrap issues. Here are two videos I took. The first video I floor it and run through a couple of gears. The 2nd is being very easy with it. The 2nd half of the 2nd video really shows how much wrap I have. I can absolutely feel all that movement. What's annoying is if I get wheel spin, be it in the rain, snow, or dirt, it'll hop really bad. I'm hoping the traction bars fix that.





I just can't imagine that removing one leaf will reduce the load by that much. Like I said, 4000 lbs and it was sitting level.

Maybe I'll just get some of those rubber spring hangers that I've seen in Diesel Power Magazine. I've read those will reduce the harshness in the rear. Maybe that'll make enough of a difference to make it comfortable.

Steve
 

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Well, I actually have some inexpensive traction bars in the garage ... The ... video really shows how much wrap I have. I can absolutely feel all that movement. ...
A picture really is worth a thousand words, isn't it?
You have a negligible amount of wind-up. Properly-installed traction bars will have a gap at the end to prevent every little bump in the road from being transmitted into the frame, and this small amount of wind-up won't even close that gap.

The lift kit is exacerbating the non-problem by giving the axle torque/thrust a longer lever arm. Either removing the lift kit, or making the lift a rigid part of the frame, would be much more effective at reducing axle wrap than installing ladder bars.


... if I get wheel spin, be it in the rain, snow, or dirt, it'll hop really bad. I'm hoping the traction bars fix that. ...
Traction bars won't have any effect when it's slick.
When it's slick and the tires slip, the tires aren't transmitting very much torque to the road. In turn, there isn't very much torque in the axle, there isn't very much torque transmitted to the leaf spring (equal & opposite reactions) and there will be even less wrap than shown in the videos.


... I just can't imagine that removing one leaf will reduce the load by that much. Like I said, 4000 lbs and it was sitting level.
If you were to remove, say, a 5-leaf spring and install a 4-leaf spring, you could expect the capacity of the spring to be reduced by 20%. (mind you, that's the capacity of the spring; the payload will be reduced by a lot more than 20% because the spring still carries the empty weight of the truck)
But that's not what you're proposing. You're proposing to change a leaf spring in which all the leaves are equally stressed into one in which one of the leaves suffers stress concentration points.
But don't rely on your imagination or guesswork; rely on physics. It's a simple calculation once you count how many leaves there are (before & after) and measure their length, width & thickness.
 

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Discussion Starter #7 (Edited)
A picture really is worth a thousand words, isn't it?
You have a negligible amount of wind-up. Properly-installed traction bars will have a gap at the end to prevent every little bump in the road from being transmitted into the frame, and this small amount of wind-up won't even close that gap.

The lift kit is exacerbating the non-problem by giving the axle torque/thrust a longer lever arm. Either removing the lift kit, or making the lift a rigid part of the frame, would be much more effective at reducing axle wrap than installing ladder bars.



Traction bars won't have any effect when it's slick.
When it's slick and the tires slip, the tires aren't transmitting very much torque to the road. In turn, there isn't very much torque in the axle, there isn't very much torque transmitted to the leaf spring (equal & opposite reactions) and there will be even less wrap than shown in the videos.



If you were to remove, say, a 5-leaf spring and install a 4-leaf spring, you could expect the capacity of the spring to be reduced by 20%. (mind you, that's the capacity of the spring; the payload will be reduced by a lot more than 20% because the spring still carries the empty weight of the truck)
But that's not what you're proposing. You're proposing to change a leaf spring in which all the leaves are equally stressed into one in which one of the leaves suffers stress concentration points.
But don't rely on your imagination or guesswork; rely on physics. It's a simple calculation once you count how many leaves there are (before & after) and measure their length, width & thickness.
First of all, I don't have a lift kit. This is 100% stock, from the factory. Last year I went back and forth with some guys on here and we finally realized that the lift block is a factory installed block. But I understand what you are saying, remove the block and that'll help with the wrap. I could remove the block and get a small lift kit (hanger) for the rear, which would allow me to keep my ride height.

I have to disagree to a point with your comment about slick conditions. I understand what you are saying, less tq to the ground, less stress. But what happens is the tires tend to grab, and release, which actually is a violent action which causes much more stress to the drive train. If the wrapping was controlled, then the tires would be allowed to just spin, not spin, grab, spin, grab.

As far as the capacity...

You can use either number you'd like, either total weight on the spring, or extra weight it can carry on top of the weight of the truck. It's all relative.

7300 lb truck. How much is on the rear while empty? Lets say only 40% is on the rear. That's 2920. Call it 3K. Now I throw 4000 lbs in the rear and the springs are holding 7K. 20% of 7K is 1400. That means I'd only be able to have a payload of 2600. That is still pretty damn good if it means I could have a nice ride.

As far as stressing the other springs more, yeah OK I could see it stressing the others, but I don't think it would be any different from driving around with a 600 lbs in the bed.


So, how about this new idea. Remove factory lift blocks and install a hanger lift kit, and remove one leaf, and forget about the traction bars all together. I have always thought the traction bars are a band aid.

Here's a picture I just snapped. 5 leafs including an overload spring at the bottom. One above that doesn't go all the way aft, stops a few inches before the hanger. What if I remove that leaf? I'd still have the overload spring for heavy loads, but 3 leafs for unloaded riding as opposed to 4?

 

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I did this exact project on my 00 model. I removed the very bottom leaf. While doing this i knew the load capacity would be reduced. Because i did not tow everyday it didn't concern me. For my towing needs i installed a set of ride rite air bags that i could manually fill when needed. Also i installed a set of sulastic shackles. So after the leaf removal i lost about 1 inch of ride height but gained half back when i installed the sulastic shackles.

The end results were exactly what i was looking for. Half ton ride quality when empty and an extremely good ride while towing.

My towing consists of a 37 foot 5th wheel approx 17k full of gear. Also towing my car hauler with roughly 10k on it.

No matter what i ever pulled it never took over 60 psi on static load to maintain factory ride height. And going down the interstate with the camper is like riding on air, literally.

I never had axle wrap problems. Running 35s wet or dry no wheel hop or anything out of the ordinary.

All who are on the fence about this mod, i would not hesitate to do it again.

Will see about posting up some pics later have to upload from the pc when at home.
 

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Discussion Starter #9
I did this exact project on my 00 model. I removed the very bottom leaf. While doing this i knew the load capacity would be reduced. Because i did not tow everyday it didn't concern me. For my towing needs i installed a set of ride rite air bags that i could manually fill when needed. Also i installed a set of sulastic shackles. So after the leaf removal i lost about 1 inch of ride height but gained half back when i installed the sulastic shackles.

The end results were exactly what i was looking for. Half ton ride quality when empty and an extremely good ride while towing.

My towing consists of a 37 foot 5th wheel approx 17k full of gear. Also towing my car hauler with roughly 10k on it.

No matter what i ever pulled it never took over 60 psi on static load to maintain factory ride height. And going down the interstate with the camper is like riding on air, literally.

I never had axle wrap problems. Running 35s wet or dry no wheel hop or anything out of the ordinary.

All who are on the fence about this mod, i would not hesitate to do it again.

Will see about posting up some pics later have to upload from the pc when at home.
That's great to hear. What kind of tongue weight do you have with that trailer? The heaviest thing I tow is my Camaro on a trailer, 5K total. I can't imagine I'd need air bags for that. So, you removed the overload spring?

Pics would be great.
 

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I did this exact project on my 00 model. I removed the very bottom leaf. While doing this i knew the load capacity would be reduced. Because i did not tow everyday it didn't concern me. For my towing needs i installed a set of ride rite air bags that i could manually fill when needed. Also i installed a set of sulastic shackles. So after the leaf removal i lost about 1 inch of ride height but gained half back when i installed the sulastic shackles.

The end results were exactly what i was looking for. Half ton ride quality when empty and an extremely good ride while towing.

My towing consists of a 37 foot 5th wheel approx 17k full of gear. Also towing my car hauler with roughly 10k on it.

No matter what i ever pulled it never took over 60 psi on static load to maintain factory ride height. And going down the interstate with the camper is like riding on air, literally.

I never had axle wrap problems. Running 35s wet or dry no wheel hop or anything out of the ordinary.

All who are on the fence about this mod, i would not hesitate to do it again.

Will see about posting up some pics later have to upload from the pc when at home.
This is exactly what I have been considering!! Did you have to buy new u-bolts or were you able to reuse them?
 

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I was able to re use my u bolts. My truck did not come with the factory upper over loads so Im not sure if that would make a difference. Also while doing it i did remove my factory bump stops to give me the extra suspension travel i was looking for.
 

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I am working on a new air ride system for HD trucks. First to hit the market is the Super Duty. I wouls lije to get some feedback. Anyone interested in a leaf spring air ride system. Make you truck ride like a cadilac and have the same load capacity. Bolt on kit that takes the average weekend warrior about 2 hours to put on. Retail will start $1700.00 and top out at $2000.00 but that also includes traction arms to stop axle wrap. Does this interest anyone???
I'll be one of your test mules.
 

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here is a pic of the truck with a load on it and only 20 psi in the bags
Looks like you need about 100 psi in the bags. That thing is draggin hiney!
 

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40 psi would have got it back level. the store air compressor would only pump to 20 so thats what i had to go with. on top of the trailer deck falling through, the tire blowing out, the spare being the wrong bolt pattern, and had to drive 300 miles to pick up the truck off the side of the road i was tired of messing with the whole deal and was just happy to get home
 

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I have 2 additional spring plies on each side, they add 1300 lbs per pairs. The spring shop that added the plies assured me that the additional ply will not ruin the ride.
I get plenty of comments on the ride of my truck as being very good compared to their own. Its that my truck mostly rides on the additional plies, 2 compared to 4. It lifts the rear a bit but not as much as air ride would.
Loaded with the 15k RV in tow they ride is very steady and comfortable.

Sent from my SPH-M910 using AutoGuide.Com Free App
 

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Well, a few weeks ago, I did the Psipower mod. I was swapping rear blocks with my father in law and figured I would pull the bottom leaf while I was in there and add a set of airbags.

I was very surprised at how much capacity I lost by pulling the thick leaf. My empty gooseneck easily put the truck on the overloads. The next day, I installed a set of Firestone airbags.

When empty, I run the bags between 5-10 psi and the ride is MUCH smoother. I wouldn't say that it's a Cadillac but it was a sure improvement. With my gooseneck of fifth wheel, I put 30 psi in the bags and it feels like I'm floating over the road.

Overall, this was a very easy mod and only took a few hours. Well worth it for me. Now that Firestone has airbags for the front end, I'm going to begin a search for softer front springs.
 

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lone star dsl, It looks like you and I have the same truck... PM sent to get a little clarification on exactly what was done for better unloaded ride while maintaining stock towing capacity. Thanks in advance for your input.
 
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