Found this on YouTube. Thought it may help to understand the way leaf springs and shackles work together. Great video! Not sure if anyone has shared this yet or not.
CK5
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Awesome Video on leaf springs and shackles
- Thread starter k5blazerguy
- Start date
I think it's kinda right, but misses a little information. If you have the shackle angle at around 90 at ride height, you are using the spring rate. If it's too stiff, you need a lower spring rate. A properly designed spring will give you a good ride at a 90 degree shackle angle. If you run the more angled shackle, more of the load is on the shocks and the springs aren't doing as much of the work.
At the end of the video he mentioned arched lift springs that are the same length as factory springs when flat. However I believe most manufacturers make the arched springs longer so that at ride height the distance from eye to eye remains the same and you don't have to relocate the shackles. But then you can end up with a shackle that is too short when the spring is compressed to flat.
Maybe @Stephen or @1977k5 can chime in with better info.
At the end of the video he mentioned arched lift springs that are the same length as factory springs when flat. However I believe most manufacturers make the arched springs longer so that at ride height the distance from eye to eye remains the same and you don't have to relocate the shackles. But then you can end up with a shackle that is too short when the spring is compressed to flat.
Maybe @Stephen or @1977k5 can chime in with better info.
He lost me at "tension spring" and "compression spring". But I'll stick with it for a few minutes anyway.
And rate has nothing to do with metallurgy unless you're using a material other than steel for your spring.
Not much mention of what happens when the spring goes into reverse arch which is super important on our trucks. Gentler shackle angles let the spring go negative. Steep angles will actually lock out the suspension when the spring is flat.
An easier way to look at this is to think about the shackle angle being set when the spring is flat and what it looks like at ride height or any other position just is what it is. With a deep arch spring that never goes flat you can play some different games but that's not much of a thing for us in the truck world.
8:15 the reason the spring is an S shape isn't because of anything to do with the shackle, it's because the leaf pack isn't built right.
9:50 shackle angle is measured compared to the eye centerline but it's done when the spring is flat.
10:30ish totally neglecting different ranges of travel. Again, come anywhere close to flat and see what happens.
11:14 "maybe you should play around with your shackle angle" This is right after he made a 100+ degree change in shackle angle. This is not a range to play in, the practical numbers are at most 25-30 degrees one way and 20 the other.
12:30ish Finally a mention of dealing with shackle angles when the leaf is flat.
14:15ish after a glimmer of home in how to measure shackle angles, we're back to something else, I don't even know what.
14:50 "you get a lot of bounce" Which is the shock's job to deal with and has nothing to do with the spring.
16:10 YES! pulling a leaf does mess up the stepping.
bottom line, you may get more droop with a bigger shackle angle but you'll give it up somewhere else, your lunch still isn't free. In our GM trucks the compression side is important. Keep your angles milder than the internet says.
You do NOT have to adjust shackle angle to accomodate a spring with more arch but the same as stock length. Maybe if you're putting 8" of arch into it but again, in our trucks milder angles work well since they let the spring go inverted.
He does have things to learn and I like that he acknowledged that.
DO NOT TAKE THIS AS GOSPEL, VERY LITTLE OF IT APPLIES TO A TRUCK. DO NOT MOUNT YOUR SHACKLES AT 45 DEGREES TO ANYTHING.
Not much mention of what happens when the spring goes into reverse arch which is super important on our trucks. Gentler shackle angles let the spring go negative. Steep angles will actually lock out the suspension when the spring is flat.
An easier way to look at this is to think about the shackle angle being set when the spring is flat and what it looks like at ride height or any other position just is what it is. With a deep arch spring that never goes flat you can play some different games but that's not much of a thing for us in the truck world.
8:15 the reason the spring is an S shape isn't because of anything to do with the shackle, it's because the leaf pack isn't built right.
9:50 shackle angle is measured compared to the eye centerline but it's done when the spring is flat.
10:30ish totally neglecting different ranges of travel. Again, come anywhere close to flat and see what happens.
11:14 "maybe you should play around with your shackle angle" This is right after he made a 100+ degree change in shackle angle. This is not a range to play in, the practical numbers are at most 25-30 degrees one way and 20 the other.
12:30ish Finally a mention of dealing with shackle angles when the leaf is flat.
14:15ish after a glimmer of home in how to measure shackle angles, we're back to something else, I don't even know what.
14:50 "you get a lot of bounce" Which is the shock's job to deal with and has nothing to do with the spring.
16:10 YES! pulling a leaf does mess up the stepping.
bottom line, you may get more droop with a bigger shackle angle but you'll give it up somewhere else, your lunch still isn't free. In our GM trucks the compression side is important. Keep your angles milder than the internet says.
You do NOT have to adjust shackle angle to accomodate a spring with more arch but the same as stock length. Maybe if you're putting 8" of arch into it but again, in our trucks milder angles work well since they let the spring go inverted.
He does have things to learn and I like that he acknowledged that.
DO NOT TAKE THIS AS GOSPEL, VERY LITTLE OF IT APPLIES TO A TRUCK. DO NOT MOUNT YOUR SHACKLES AT 45 DEGREES TO ANYTHING.
Please clarify. In all cases, all load is on the spring.
Probably not really worded the best. I would say the shock has to do more dampening work with the angled shackle.
I wish I had read the responses before I watched it. I was ??????????????????
Maybe they work differently on International farm tractors.
Maybe they work differently on International farm tractors.
Thanks Stephen! Appreciate your response and clarification on that. Do you have a YouTube channel? Would be great if you did tech videos.
Been reading a few articles and I realize there are tons of posts on the topic, I can not get my 89' Jimmy to feel tight but not harsh. It does well for a fairly stock truck with a couple ORD HD upgrades off road, however driving the freeways to and from places you can drive OHV trails is a sh*t ride. Hard to describe almost like a harsh boat ride. wallowy
2" Tuff Country EZ Ride Front 3" Tuff Country EZ Ride Rear ORD HD Front shackles and 4 1/2" ORD rear super shackles Both at 90* angles ORD Steering Brace ORD Sway Bar disconnect
Bilstein 5125 front and rear shocks Not sure valving but purchased from ORD with th Springs
2" Tuff Country EZ Ride Front 3" Tuff Country EZ Ride Rear ORD HD Front shackles and 4 1/2" ORD rear super shackles Both at 90* angles ORD Steering Brace ORD Sway Bar disconnect
Bilstein 5125 front and rear shocks Not sure valving but purchased from ORD with th Springs
These are the angles pretty close to 90° for the shackles and the shock position I’m using
Your current shackle angle is actually pretty good front/rear, changing that won't make it ride better
Will shocks with different valving help or will I have to get more progressive springs
The harsh stiffness is caused by springs the soft boat ride by not enough shock dampening? Should I get the ORD front shock extenders and change the angle?
If I were to spend the money on custom ORD springs I'm guessing it would be softer but then I would need stiffer shocks?
I know it wont ride like my 2012 tahoe but it seems like I could tame it a bit without getting to harsh a ride. I would prefer to eliminate the boat jello spongy feel and have stiffer ride.
However ultimately I would like it to ride better than when it was stock.
My 77' rode a bit stiffer but very tight no "boat" feel
Sorry for all the novice questions and thank you for help
The harsh stiffness is caused by springs the soft boat ride by not enough shock dampening? Should I get the ORD front shock extenders and change the angle?
If I were to spend the money on custom ORD springs I'm guessing it would be softer but then I would need stiffer shocks?
I know it wont ride like my 2012 tahoe but it seems like I could tame it a bit without getting to harsh a ride. I would prefer to eliminate the boat jello spongy feel and have stiffer ride.
However ultimately I would like it to ride better than when it was stock.
My 77' rode a bit stiffer but very tight no "boat" feel
Sorry for all the novice questions and thank you for help
My blazer felt like I was driving a water bed. I put on the ORD 5125 bilsteins and it feels great. Not too stiff but not a water bed either. Can’t guarantee thier valved bilstein shocks will fix your ride but they did for me.
My shocks on the front and rear are installed in the stock positions with a 4” lift. 9.24 travel in front with 11travel in the rear.
These trucks I doubt will ever ride like a Cadillac
My shocks on the front and rear are installed in the stock positions with a 4” lift. 9.24 travel in front with 11travel in the rear.
These trucks I doubt will ever ride like a Cadillac
The heck is this guy's problem with Yellow. Yellow is awesome.
I have the 5125 Bilsteins in the (stock rear more slack) position.
Most of the other members say to go single so I got rid of ranco duals
Needing some help with my rear shackle set-up on the Xterra. It's sprung under and I'm not sure of the math to check my shackle angle and order new springs eventually.
My Alcan leafs are bending in front of the axle. I believe this is because of axle wrap. But I'm approaching their weight limit.
I'm going to need stronger springs but I'm wanting to keep the longer rear shackle for better articulation. But I need to better understand shackle angle in this instance so I know the lift/capacity specs I need to
order.
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It would really help if the shackle was in the picture.
Needing some help with my rear shackle set-up on the Xterra. It's sprung under and I'm not sure of the math to check my shackle angle and order new springs eventually.
My Alcan leafs are bending in front of the axle. I believe this is because of axle wrap. But I'm approaching their weight limit.
View attachment 447921
I'm going to need stronger springs but I'm wanting to keep the longer rear shackle for better articulation. But I need to better understand shackle angle in this instance so I know the lift/capacity specs I need to
order.
Here we go. I think the angle is really good right now, but I'm concerned it'll be too vertical once I get leafs with more arch in them.
I'm looking for about 4" total lift and wanting to have 3" lift in the leaves and run the lowest setting on these for about 1" lift but a longer, more active shackle offroad.
This is the best picture I have of full droop. I have a few more inches of down travel I'm hoping to open up with the new shocks I'm getting today.
I'm looking for about 4" total lift and wanting to have 3" lift in the leaves and run the lowest setting on these for about 1" lift but a longer, more active shackle offroad.
This is the best picture I have of full droop. I have a few more inches of down travel I'm hoping to open up with the new shocks I'm getting today.
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