Can anyone recommend a way to soften the ride a bit on a new 2500hd? I have towed next to nothing prior to buying this and just loved the motor so much I bot the stiffer truck in order to have it (first diesel ever).


I do not want to lose any of the weight-handling abilities with the existing leaf springs,etc but if there is a way to modify the truck so that when it is running in light condition with no cargo it won't bounce around as much.





Thanks

Don't think you're gonna win on this one the way you want to. Some guys are removing one leaf out of the back, but that reduces your load bearing capacity. You might try removing the leaf and adding air-bags to her, I don't know how that would ride though. Good luck!

You should check out the Mor/Ryde RL (Rubber Leaf) system.


www.morryde.comEdited by: Dave Stevens

Three words, four numbers, Rancho 9000 adjustable shocks. Put them on the softest setting in back for an unloaded ride and stiffest setting for the big loads. Leave the front adjusted on about the middle setting. Worth there weight in gold for these situations. I carry a 4000+ lbs camper some times. Don't try it with stock shocks, unless you enjoy pogo sticks. Then there to harsh for unloaded use. They make a big differance on the spine. Super Diesel

Bilsteins up front and Rs9000's in the rear(only if you do actually haul) otherwise Bilsteins all the way around!!!!

Billsteins cut the oscillataion out of my truck ride when emptyhttp://www.dieselplace.com/forum/smileys/Approve.gif

I've got a 3500 but the ride is pretty similar to the 2500. What I did so far is : add the RS9000s, added velvet ride shackles, removed upper overloads, removed lower overloads, and the longest removeable leaf.


I have a set of air bags that I'm going to add next to restore load carrying capacity.


I added a couple 1.5 inch lift blocks to compensate for the removed springs and the rear still sits about an inch low due to the spring arch being less now. This is about perfect for adding the airbags which should bring the rear up about an inch or so at 5psi.


Not sure what your biggest complaint is, but mine was the intense shock that came from the back when hitting a moderate bump, and the constant surging from the back on the highway.


That shock is gone now and the highway ride is nice. If I were starting it again, here is what i might try:


Remove upper overloads if equiped, flip lower overload upside down, install RS9000s.


Oh and make sure your tires are at 60psi min in back (on a dually). Lowering the pressure makes the ride aweful. not sure about pressure on a 2500.


Good luck


jeff


Edited by: ZZ4x4

Drop the tire pressure especially in the back if you arnt running loaded. If you run around with 80psi in an unloaded truck it will ride like a log waggon. Tires load rating is based on its max pressure. For simplicity lets say a tire is rated for 1000 pounds at 100psi. If you are only putting 500 pounds try 50psi. Its much better to be overinflated than under. Remember that you have 4 tires and the fronts have more weight genneraly than the backs. Also remeber to account for the family and a tank of gas. Like I said its better to be over than under.

Also remeber that you need to go by the tires not the door sticker if you dont have the factory tires. Every tire is different......

The factory springs are said to have spring rate of 350 lb/in till overload contact, then 750 lb/in thereafter. There is only 1/2" of travel to overload contact.





In order of effectiveness, on my HD


2500HD


1. Remove, rearch, or flip the bottom overload spring. (Rearch or flip to avoid a 1" drop in height) Eliminates bucking on every bump. I rearched flat, and you don't have to pay for new u-bolts that way. Flipping it is the cheapest way to go, same result, just more sag under very heavy loading. $50-75 at the local spring shop, or easy DIY project, don't even have to remove the springs.


2. Remove next lowest leaf, the one on the bottom of the 4 leaf pack. This is the one with the greatest spring rate reduction. Nice carlike highway ride with about 1" drop. Most noticeable comfort is on highway for me


3. Airbags-restores HD carry capacity, without HD ride. 5-10 psi = stock ride height.


If you are not lifting the front, then removing the overload may give you a nicer ride height in back. In any event, airbags are said to remove some of the metal leaf harshness, but for a more compliant ride, leafs must be modified to lower spring rate. The bags are said to work best, as indicated in the engineering data, at a 7" height, which is about 1/2"-1" above factory height. 5"-7" is acceptable. If you lower the vehicle 2" first, then 20-25 psi will be required to get it up that high (7"), and most of the empty bed weight will be on the bags, not the springs.Edited by: masterp2

I installed RS9000s on all corners and made a big difference. I then added airbags to the back and put in about 15lbs. The truck rides 75% better than the stock. The wife and kids like driving in the truck again.http://dieselplace.com/forum/smileys/Big%20Smile.gif

....and you ride about 1-2" higher in the back. The airbags elevate the main spring pack above the overload spring, keeping you from consistently hitting stage 2.

Is that a good or a bad thing? I have heard of people doing this and I don't think it hurts anything. I think that Airlift recommends keeping 5 psi in the bag when unloaded anyway...

Nothing wrong with it. http://www.dieselplace.com/forum/smileys/Approve.gif But if you keep a stock height front end, you will resemble a funny car. The back will be 5" higher than the front. So removing the overload and/or a leaf, can help compensate for the height increase that results from airbags ride improvement.


I have 2" lifted front, and with airbags on a stock rearend, the truck still would be unlevel, higher in the back with 5-10 psi. Just some lift considerations. If you plan a level lifted truck, to get bigger rubber underneath, plan on removing something from the leaf settup. I prefer the idea of leaving the dearched (or flipped) overload and removing a leaf. Ride is superior, the overloads are still there to handle a heavy load if the bags fail, and truck is nearly level when filled to 10 psi, a noted ride comfort setting. Flipping the overload is easy, removing a leaf, not so easy, pack must be removed, but you don't have to get new U-bolts.


http://www.dieselplace.com/forum/uploads/257_side.jpg


This is minimum torsion lift for 315's, H2's, about 2" or less. The back has had overloads dearched and one leaf removed, it is about 1" or so lower than front. When bags are installed, it will be restored to level, or slightly higher in the back. Some planning here.


Some folks need to keep the back end down, towing restrictions. This also allows you to lower the back using airbags, loading the bed is easier for example.Edited by: masterp2

Masterp2,


Just curious about your thinking / analysis on the removal of the lowest leaf (above the overload) vs. say the uppermost removeable leaf. I was thinking about it and couldn't really come up with a clear advantage for one or the other. I chose removing the upper but might switch it the other way if there is good reason.


I thought that by removing the uppermost spring, I am allowing the top spring to flex a little (soaking up minor road imperfections) before the main spring pack reacts although when it does react it will be a little more abrupt. By removing the lowest leaf, I imagine i'd have a slightly firmer ride but a more progressive spring rate. All of my thinking usually goes out the window when I try something and find it doesn't react like I thought it wouldhttp://www.dieselplace.com/forum/smileys/Confused.gif. There are a lot of variables, such as shock valving setting (RS9000s), unspring weight, tire pressure ,DRW vs SRW.


Do you have the airbags running? If so , in your opinion, was there any real difference in the feel , or was the difference in the spring changes ( the airbags just raising the rear).


Thanks,


jeff

I am installing the airbags this week, no personal experience, though I have researched the engineering data to determine a predictable response, when they are added in parallel to the leafs. And if too much air is necessary to level the ride, i.e. the truck is lowered too far beforehand , spring rate will increase dramatically. If the bags are not inflated to at least 6.5", spring rate will increase too soon in the compression travel. So there is a bit of a tweaked happy medium. I am going to error to the side of taking more weight of the leafs, because I think much of the ride quality value of bags is the removal of interleaf friction and harshness, both a function of the weight they handle. Also, the spring rate of the relaxed leaf pack is somewhat reduced at a static height closer to it's unloaded deflection.


To answer your question, though, the short answer is that my spring shop recommended the lower leaf removal. In my mind, I think removing the lower leaf does 2 things. Allows the pack to flex more (????), and reduces the "rate" of the pack more. Why? In reality all of them are close to the same length, not very progressive at all, these are not deaver. But one thing that is observable is that the lower leafs are always arched more, look at a pack torn apart, and so when all are bound together, the lowest one has the greatest deflection arc and therefore adds the most to spring rate of the pack unit (assuming length diffs are negligible). Since spring rate reduction is the goal, there you have it.


I know some have removed the longest removeable, and don't know if there is other logic for that. But what is clear to me in the quest for empty ride comfort, is that reducing spring rate in the first part of travel, while providing a progressive rate is ride comfort. Just adding bags, increases overall rate, and progressiveness, especially at about 3 inch deflection.


Airlift super duty bags:


http://www.goodyearindustrialproducts.com/airsprings/pdf/2B6-535.pdf


http://www.dieselplace.com/forum/uploads/airlift_data.png


The tab data is taken from the curves. Curve L1 represents about 10-20 psi in our application of this bag. L5 is around 100 psi. The y-axis, load, is the response of the bag to being compressed (oe extended) from the design height. Pick a curve and ride on it beginning at design height, and the dynamic effect of road obstacles shows how the bag reacts. Beginning with 60 psi in the bag, a hard bump can increase the pressure to 200+ psi, and with that nearly constant cross-sectional area of the bag, enormous spring forces are produced. See how flat the curves are from 5-7" ? Then tremendously exponential as they compress past 5". At 3.0" (close to bump stop contact if no airbags), a 40 psi bag has a spring rate of 3000 lb/in EACH (slope of the curve at that point), after only 3" of travel. Which is great with 4000 lb camper, but with an 1800 lb bed only over them, bouncy. Easy to see why they only warranty the bags with a min psi in them. They protect themselves with even a little bit of air, with massive spring rates at compressed condition. I want to stay as high as possible in the static "design height", so that I have some significant travel before encountering these massive rates on compression.


The tab data says it too. The same bag supporting 500 lbs at static design height has 50% greater rate than if it were supporting same at 7" height (245 vs 360). [b]So I am a 6.5" or 7" man for ride com

Thanks for all the info. You have really looked into this topic. Good luck with your airbag install. Post some pics if you can....

Yes, thanks MasterP2. I am very interested at your outcome. We too are looking for a better ride in our D/A CC LLY. Talked with Deaver and they recommended the flip of lower overload and even possibly removing one of them.. They did tell me do the bags to be sure that I can still haul what I need to and to get an even better ride. Do you mind if I ask a question in lamens terms? You stated that in theory if I want to add airbags, I should have the truck sit about 2 inches lower than I truly want it to sit (by removing and flipping leafs) then add the airbags with air pressure in them. The truck will actually use a portion of the airbag for suspension before using the spring pack for additional suspension? Did I understand you correctly? I just want to be sure I understand the concept correctly before I go to my tire shop and start having them start trying things. Also, you mentioned you are using Ranchos 9000x's. What model did you purchase? Did you use spacers on the front? Do you think that helped with upward motion? Just curious. It appears as if you have done the type of research on this subject and I really would like to hear you opinions on this. I am looking for the impossible, a D/A that rides like a 1/2 ton. I know it won't happen, but I want to know that I did what I could...


Thanks in advance,
Jarrod

MasterP2 - I guess I should have read your sig better - seems you have bilsteins not Ranchos... Sorry about that...

I use bilsteins, modified with spacers, absolutely necessary when lifting. If you are at 2", use 2" worth of spacers, if possible. see


http://www.dieselplace.com/forum/forum_posts.asp?TID=9925&KW=masterp2


and


http://www.dieselplace.com/forum/forum_posts.asp?TID=9411&KW=masterp2


As for the back, it is important to acknowledge that leafsprings are designed to operate properly over a specific rage of arc, part of this has to do with the motion required of the swing shackle on back. It needs to stay in a specific range of motion, over the pivot, as the leafs elongate and shorten during articulation. Removing a leaf would allow staic height elongation and put the pack in a different, longer, static "length". A short shackle would be more bouncy than a longer lowering shackle. Picture it, after the shackle pivots past about 20 deg from vertical, the vertical length of the shackle changes rapidly, hence, adverse forces on the spring pack that cause it to be bouncy at the bottom of the stroke. But be careful with longer shackles if you plan heavy loads, they present another tradeoff in that a longer shackle recieves more lateral stress than a shorter one.


Lift it an inch or 2, using bags, to the factory tuned arc and that becomes 1-2" extra travel before reaching that bouncy phenomenon, which I think is observable. The bags will restore this height after a leaf is removed, or shackle mod. In doing so, you reduce, not entirely remove, the weight on the softer springs and further reduce it's spring rate, by how much I do not know. I have yet to come up with curves for leaf springs. What is certain is that the airbags are going to ADD at least 150-200 lb/in to the static height spring rate, and greatly enhance the leafs progressiveness (sports car), while reducing interleaf friction (harshness). Minimizing the combined (added) spring rates at static height is my goal, without compromising too much on other things. It was hard to let the leaf go but I think worthwhile with the bags, we'll see. the D/A with a non-bonejarring ride is really impressive, but not for everyone I realize.


Remember the other function of leafsprings. They provide the lateral force to keep that load behind you in an evasive action turn, for example. Bags do not compensate for leaf removal. I don't know what the effects of removing a leaf is on that capability. Wheel hop/axle wrap can be a factor as well. High torque capabilties demand stiff springs, find your compromise.


The ride is very improveable, I am still finding improvement and am very impressed so far. Not quite a 1500 but very close. I am going for the sports car ride, very mellow highway ride with cornering and traction capabilities, all in a vehicle that will still haul 10K in comfort. Off-road, I think it would be an improvement also, with respect to articulation and washboard tolerance. I am at the point of diminishing returns, I'll get the bags on and post any diffs. I wish I had an accelerometer and a dirt road so I could quantify these changes.


Edited by: masterp2

There is a group buy for the Edge Juice/attitude for the LLY, looks like you need one. Post some pics of your truck.


I think it worth re-mentioning again the importance of retaining the overload if possible. Flipped, it's not very useful because of the arch, basically a shim. If the bags failed under load, it would not protect them. i now consider them my bump stops. I just got lucky here in phoenix, the spring shop dearched them for free, in return for feedback.. I am becoming a good customer at Valley spring.

Michael,


I do plan on flipping the overload to start with. I am unsure if I will remove one of the other springs in the pack. Still trying to stay as "warranty" friendly as possible. When is the Attitude LLY module coming out? I am definately interested as long as the "footprint" can not be noted by the dealer. Pics to come soon. I haven't had a chance to "part" with it so the front can be colormatched yet (waited so long for the custom order)...I may take an interim shot and post them. Let me know about that Group Buy..


~Jarrod

se7enracing


You have mail. I will say that the leaf removal was very apparent on smooth roads/ highways, cannot feel those cracks any more, does smooth it out some and a closer match to the front compliance. But on deeper dips, I think the springs are too straight and are forcing that shackle out to far. I installed the bags to "rearch" the springs in the static condition. Now the highway ride and the bigger dips have improved, with 2" more compression travel than a "leaf removal only". These mods have proven so comfortable (and practical), I think GM should offer it as an option. makes me want to go shopping for a camper. Funny, I'm a Boston boy, my wife from Paola, (podunk)Kansas, she thinks I'm turning into one of those hometown boys she turned down.