Kelderman 4-Link
Well, I'm back after a bit of a hiatus and starting to think about TC's again. Had a big 5th wheel for a while after selling the S&S back in 2010, then sold the 5'er to finance building a garage, but...
Forum Discussion
Hey guys - thanks for the heads'up.
Mooney indeed had a 4 bag system from Link. He loved it and was pretty pleased with how it did off-road. That was one of my concerns when I was looking into the air system for my Kodiak. Another engineer on the forum that bought one got a hold of the designs specs and really put the pen to paper so to speak on the engineering design and he also gave it the thumbs up. However, for my application on a Kodiak, they had a different system. I can't remember for sure if it was a 4-bag system or 2 (I think it was two) or not, but it was laid out in a completely different manner than the Ford kit. Instead of their being a cross member up high under the bed, it was much more exposed and below the axle and not nearly as well laid out as the Ford kit. When I talked to Link and explained my application, he ended up saying that he would also be concerned about it swaying more than I'd like in extreme crosswinds.....and "much as I hate to recommend not buying our product, I'm just not sure it's the right thing for your application." He said most guys getting them were using them on hauler chassis for highway use and they work great for that. Since it was still the kind where you completely remove the leaf springs, it is a complete/total change and at the high dollars we are talking about, I decided it was a risky choice. Especially if doing any 4x4'ing. The bags were way exposed at the back and low and I could totally see backing them into a rock and damaging them. For a highway application, even with the height, I bet it would still be fine (at least on my heavy heavy truck despite what the guy said.) It was the 4x4 aspect mostly that scared me off.
The other option was Kelderman. They have two kinds of systems for my Kodiak (at least....) One is a 4 bag system, that looked pretty similar to what Link had (replace leaf springs, bars and bags down pretty low and exposed etc.) The other was a sort of in between system. Basically in concept, you replace the entire rear shackle mount with a new mount, that integrates a heavy duty air bag and then has a new beastly shackle. So the air-bag rides between the spring eye, and the frame which means it has sort of a two-stage spring system. The idea is that the small bumps and hits can mostly be taken up by the air bags, and the heavy hits or twists will compress the spring. I liked that idea, plus the system is pretty well protected and doesn't reduce the ground clearance at all. Plus, it seemed like a less drastic change not losing the spring itself.
How has it worked? It does pretty much exactly what I wanted, and has substantially reduced the harshness on the rear of the truck. There are a few drawbacks to it, but overall I have been happy with it.
Pros:
It has really softened up the rear. I did it primarily to reduce the stress on the poor Lance that has now been driven 105,000 miles, from Maryland to Argentina and back and all over the mountain west, and had about 750 nights of camping in it. I used to hit bridge ends and the truck would go BAM, BAM as the front then rear went across. Now it goes BAM, bam as the rear is a lot softer.
Sway is nearly non-existent....maybe the slightest bit more than before, but there was so little to start with that it is a non-issue. When I poass semi's going the opposite way on a 2-lane road, I basically don't even feel it. I hear it, but only a very rare semi causes enough wind-wall for me to feel it. To be honest though, it never did before either and I attribute that more to the size and design of my truck than the Kelderman system; however, the system did not increase it much at all if any.
I still feel it hasn't reduce my off-road ability at all (not that I have that much anyway, but still....); the bags are safe and well protected and don't hang down much at all.
I hooked it up with in-cab controls, and also hooked it up tied together (via a one-way valve) to my existing air system that has a 5 gallon air tank and I also put in several valves so that I can isolate one part of the system from another, and even cutoff the airbags from the system and add air directly to the bags (via another air port) if I ever lost a line and couldn't hold air.
Cons:
1) The biggest one is that my springs are "slipper" springs, which means rather than a spring eye at the end, it has straight ends to the springs, which slip through the shackle rather than be bolted. My springs are....well......"tired" lets say. They have become a bit flattened from having a minimum of 1000 pounds more than GVWR and currently about 2000 pounds over designed GVWR. And I carry that weight 95% of the time. Possibly because of that, but partially because of the design, the ends of the spring can hit the bag mount if I have the wrong amount of air pressure. So when driving at least (which causes the spring to flatten and lengthen) I have a relatively small range of air pressures I can work with at least when loaded. I run from 95PSI to about 125PSI. The high end when traveling with my 300# dirt bike on the bumper, or when pulling my heavier dump trailer with the skidsteer in it (about 6000 pounds) with the camper on.
2) If I lost an air bag, I'd pretty much be screwed. I have some hope that I'd be able to jack up the bed/chassis and insert an 8"x8" block of wood between the axle and the frame or some other hack job to limp back in solid suspension mode. Not sure how it would work if at all. The jerks at the install place did NOT give me my shackles back so I wouldn't be able to try to put back in the original somehow, but truth-be-told I'm not sure if that would have been feasible anyway.
3) The air bags are remarkably soft when not in motion. What that means is despite the extreme size/weight of my rig when I climb into the camper at night after hanging out by the fire, I shake the rig so much I wake up my wife. It is that soft and sensitive to minor weight shifts. I've gotten more in the habit of dropping the rear jacks when I set up camp to stabilize the camper.
4) Cost. I didn't add it all up, but it was 5K+ for sure. Probably more like 6, but that also included the extra stuff I made them do with tying into my existing air system. Partly it was exaggerated because the bozos I had do it told me the compressor I had wasn't up to the task and I had to get one with their system.....but not the expensive one Kelderman sells. Turns out that the old one I had was actually BETTER and more POWERFUL than the one that came with a firestone kit. So he made me buy a whole kit, probably just for the gauges and accessories, and I didn't even need the extra compressor. Keep in mind I already had the stock one that runs the air seats and the exhaust brake. So now I have 3 compressors that are so-so and a complicated line and valve system that cost them a lot of extra work, and me a boatload of additional trips to the shop to finally get it to the specs I had planned in the beginning. I'd rather have one awesome compressor running all of that, and the original stock compressor just used for the seats and e-brake, and maybe an emergency crossover between the systems.
5) Installers. The guys that did mine, have done many of them before, but each one is different. My frame was modified by the original owner (they chopped off a short bit of frame at the back) and it had a Reese Tow Beast installed. The kit I bought from Kelderman had the hitch built-in so it cost extra but I went that way because we weren't sure if we could reuse my old one or not. But with the way things on my truck were, they had to end up improvising, the hitch that came with they hacked out and they tied in to the Reese I already had. That wasted the couple hundred I paid for the hitch. In the end, I think they worked out a pretty good solution, and it appears to be beastly strong....but damn, if I had it to do all over again I wouldn't have tried to do this right before a 5000 mile trip to Vancouver Island (though it was great on all those logging road bridges that had brutal hits when you get on them) and I would likely take it directly to Kelderman. They are in Iowa I think, and not that far for me.
What about moving forward? What changes would I like to make?
Mainly I'd like to replace my springs. They are beat and tired, and too flat. I'd like to change them to an eye type spring to avoid the slipper end being able to hit the mount when at the wrong pressure or from an extreme hit on the suspension. That would have to include a whole new "shackle" for the eye-type spring. I'd also like to have some sort of emergency rig that I could do if I ever lost a bag. Not sure how I'd do that. But no matter what sort of change I might make, I think I'd be taking it to Kelderman to do the changes and not mess with a local installer. I'd also like to change the stock shocks out (many Kodiak owners change them right when they buy them; mine have 105K rough driving on them. They too are tired and beat. I'd buy springs from Deaver Springs in SoCal along with the King shocks that they use. Just dreaming here, but it would be a big improvement I think.
I have plenty of pictures I could post, but the thing is, I expect my system is not the same as they have for a one-ton regular truck. Let me know if you want me to. They may not have the "shackle replacement" version for you. I'd get the plans from Kelderman and talk to them. They were good on the phone with me, and have pretty good install guides that show how the kits are made. The biggest thing I'd watch out for is the ground clearance. Most people are getting these for highway hauling, not for off-road.
Auto-leveling? I wouldn't personally want to mess with it. Too complicated and once you find the pressures you need to run you don't need it. If you lose air, how do you turn it off? What if level isn't what you need based on pressures/load/clearance/whatever. What if you want to level it at a parking spot? What if you are on a hill? Does it try to level it? I don't know much about how they work, but I'd ask these questions. In-cab controls? Absolutely! But probably not auto-leveling depending on how they work.
Not sure if I answered all your questions. I've been pretty busy lately and not reading rv.net a lot lately, but let me know if I missed follow-up on this thread via PM and I'll come back out and answer or post pictures, whatever.
In the meantime, "Boiler up!"
Mooney indeed had a 4 bag system from Link. He loved it and was pretty pleased with how it did off-road. That was one of my concerns when I was looking into the air system for my Kodiak. Another engineer on the forum that bought one got a hold of the designs specs and really put the pen to paper so to speak on the engineering design and he also gave it the thumbs up. However, for my application on a Kodiak, they had a different system. I can't remember for sure if it was a 4-bag system or 2 (I think it was two) or not, but it was laid out in a completely different manner than the Ford kit. Instead of their being a cross member up high under the bed, it was much more exposed and below the axle and not nearly as well laid out as the Ford kit. When I talked to Link and explained my application, he ended up saying that he would also be concerned about it swaying more than I'd like in extreme crosswinds.....and "much as I hate to recommend not buying our product, I'm just not sure it's the right thing for your application." He said most guys getting them were using them on hauler chassis for highway use and they work great for that. Since it was still the kind where you completely remove the leaf springs, it is a complete/total change and at the high dollars we are talking about, I decided it was a risky choice. Especially if doing any 4x4'ing. The bags were way exposed at the back and low and I could totally see backing them into a rock and damaging them. For a highway application, even with the height, I bet it would still be fine (at least on my heavy heavy truck despite what the guy said.) It was the 4x4 aspect mostly that scared me off.
The other option was Kelderman. They have two kinds of systems for my Kodiak (at least....) One is a 4 bag system, that looked pretty similar to what Link had (replace leaf springs, bars and bags down pretty low and exposed etc.) The other was a sort of in between system. Basically in concept, you replace the entire rear shackle mount with a new mount, that integrates a heavy duty air bag and then has a new beastly shackle. So the air-bag rides between the spring eye, and the frame which means it has sort of a two-stage spring system. The idea is that the small bumps and hits can mostly be taken up by the air bags, and the heavy hits or twists will compress the spring. I liked that idea, plus the system is pretty well protected and doesn't reduce the ground clearance at all. Plus, it seemed like a less drastic change not losing the spring itself.
How has it worked? It does pretty much exactly what I wanted, and has substantially reduced the harshness on the rear of the truck. There are a few drawbacks to it, but overall I have been happy with it.
Pros:
It has really softened up the rear. I did it primarily to reduce the stress on the poor Lance that has now been driven 105,000 miles, from Maryland to Argentina and back and all over the mountain west, and had about 750 nights of camping in it. I used to hit bridge ends and the truck would go BAM, BAM as the front then rear went across. Now it goes BAM, bam as the rear is a lot softer.
Sway is nearly non-existent....maybe the slightest bit more than before, but there was so little to start with that it is a non-issue. When I poass semi's going the opposite way on a 2-lane road, I basically don't even feel it. I hear it, but only a very rare semi causes enough wind-wall for me to feel it. To be honest though, it never did before either and I attribute that more to the size and design of my truck than the Kelderman system; however, the system did not increase it much at all if any.
I still feel it hasn't reduce my off-road ability at all (not that I have that much anyway, but still....); the bags are safe and well protected and don't hang down much at all.
I hooked it up with in-cab controls, and also hooked it up tied together (via a one-way valve) to my existing air system that has a 5 gallon air tank and I also put in several valves so that I can isolate one part of the system from another, and even cutoff the airbags from the system and add air directly to the bags (via another air port) if I ever lost a line and couldn't hold air.
Cons:
1) The biggest one is that my springs are "slipper" springs, which means rather than a spring eye at the end, it has straight ends to the springs, which slip through the shackle rather than be bolted. My springs are....well......"tired" lets say. They have become a bit flattened from having a minimum of 1000 pounds more than GVWR and currently about 2000 pounds over designed GVWR. And I carry that weight 95% of the time. Possibly because of that, but partially because of the design, the ends of the spring can hit the bag mount if I have the wrong amount of air pressure. So when driving at least (which causes the spring to flatten and lengthen) I have a relatively small range of air pressures I can work with at least when loaded. I run from 95PSI to about 125PSI. The high end when traveling with my 300# dirt bike on the bumper, or when pulling my heavier dump trailer with the skidsteer in it (about 6000 pounds) with the camper on.
2) If I lost an air bag, I'd pretty much be screwed. I have some hope that I'd be able to jack up the bed/chassis and insert an 8"x8" block of wood between the axle and the frame or some other hack job to limp back in solid suspension mode. Not sure how it would work if at all. The jerks at the install place did NOT give me my shackles back so I wouldn't be able to try to put back in the original somehow, but truth-be-told I'm not sure if that would have been feasible anyway.
3) The air bags are remarkably soft when not in motion. What that means is despite the extreme size/weight of my rig when I climb into the camper at night after hanging out by the fire, I shake the rig so much I wake up my wife. It is that soft and sensitive to minor weight shifts. I've gotten more in the habit of dropping the rear jacks when I set up camp to stabilize the camper.
4) Cost. I didn't add it all up, but it was 5K+ for sure. Probably more like 6, but that also included the extra stuff I made them do with tying into my existing air system. Partly it was exaggerated because the bozos I had do it told me the compressor I had wasn't up to the task and I had to get one with their system.....but not the expensive one Kelderman sells. Turns out that the old one I had was actually BETTER and more POWERFUL than the one that came with a firestone kit. So he made me buy a whole kit, probably just for the gauges and accessories, and I didn't even need the extra compressor. Keep in mind I already had the stock one that runs the air seats and the exhaust brake. So now I have 3 compressors that are so-so and a complicated line and valve system that cost them a lot of extra work, and me a boatload of additional trips to the shop to finally get it to the specs I had planned in the beginning. I'd rather have one awesome compressor running all of that, and the original stock compressor just used for the seats and e-brake, and maybe an emergency crossover between the systems.
5) Installers. The guys that did mine, have done many of them before, but each one is different. My frame was modified by the original owner (they chopped off a short bit of frame at the back) and it had a Reese Tow Beast installed. The kit I bought from Kelderman had the hitch built-in so it cost extra but I went that way because we weren't sure if we could reuse my old one or not. But with the way things on my truck were, they had to end up improvising, the hitch that came with they hacked out and they tied in to the Reese I already had. That wasted the couple hundred I paid for the hitch. In the end, I think they worked out a pretty good solution, and it appears to be beastly strong....but damn, if I had it to do all over again I wouldn't have tried to do this right before a 5000 mile trip to Vancouver Island (though it was great on all those logging road bridges that had brutal hits when you get on them) and I would likely take it directly to Kelderman. They are in Iowa I think, and not that far for me.
What about moving forward? What changes would I like to make?
Mainly I'd like to replace my springs. They are beat and tired, and too flat. I'd like to change them to an eye type spring to avoid the slipper end being able to hit the mount when at the wrong pressure or from an extreme hit on the suspension. That would have to include a whole new "shackle" for the eye-type spring. I'd also like to have some sort of emergency rig that I could do if I ever lost a bag. Not sure how I'd do that. But no matter what sort of change I might make, I think I'd be taking it to Kelderman to do the changes and not mess with a local installer. I'd also like to change the stock shocks out (many Kodiak owners change them right when they buy them; mine have 105K rough driving on them. They too are tired and beat. I'd buy springs from Deaver Springs in SoCal along with the King shocks that they use. Just dreaming here, but it would be a big improvement I think.
I have plenty of pictures I could post, but the thing is, I expect my system is not the same as they have for a one-ton regular truck. Let me know if you want me to. They may not have the "shackle replacement" version for you. I'd get the plans from Kelderman and talk to them. They were good on the phone with me, and have pretty good install guides that show how the kits are made. The biggest thing I'd watch out for is the ground clearance. Most people are getting these for highway hauling, not for off-road.
Auto-leveling? I wouldn't personally want to mess with it. Too complicated and once you find the pressures you need to run you don't need it. If you lose air, how do you turn it off? What if level isn't what you need based on pressures/load/clearance/whatever. What if you want to level it at a parking spot? What if you are on a hill? Does it try to level it? I don't know much about how they work, but I'd ask these questions. In-cab controls? Absolutely! But probably not auto-leveling depending on how they work.
Not sure if I answered all your questions. I've been pretty busy lately and not reading rv.net a lot lately, but let me know if I missed follow-up on this thread via PM and I'll come back out and answer or post pictures, whatever.
In the meantime, "Boiler up!"
