I’m seeing some mixed reviews in reading about pros and cons of various dump truck suspension types. Traditionally, it seems air ride is not ideal for rugged construction sites. But it seems like there are some contradicting reports about newer air ride systems. Have they developed better technology or are construction dumps still better suited to the traditional suspension types?
I'm a die hard-Hendrickson built the RTE for one reason, and it wasn't a soft ride. Want that buy a Cadillac.
Air ride is not intended for off-road use IMHO - off-road defined as anything that is not an asphalt or concrete surface. If the suspension manufacturers want to say different then they are bullsh1tting.......... HeavyEquipmentForums
Pandering for sales.
Trying to convince people who don't know any better more like.
No air suspension on a dump for me. Chalmers 800 would be my choice.
You can only inflate a balloon so many ways and only so many PSI.
Thanks guys good info. I saw the tippy picture above and it reminded me of a dream I had last night , I bought a new truck and kept flopping it over every time I dumped. Lol. I found a 2022 HX 520 but it’s air ride. Obviously not much availability out there but I’ll have to skip over the air ride.
All our tractor trailers are air ride, both truck and dump trailer, and float trailers as well. Mind you off road to them is a gravel haul road, and you still need a level spot to dump a trailer. The bags on the trailers dump when you open the tailgate, I always dump the bags on the tractor, but not everyone does. Not so much for stability, but I don't like the idea of all that weight coming off the bags at once. A few private owners have air ride on strait trucks. We have one converted tractor that still has air ride. I am always careful where I dump a trailer, but I have no fear of dumping a leaning strait truck, as long as I know the gate is open. As an after thought, all the wood haulers here run air ride as well, and they are always wallowing in the mud. As far as spring suspension goes, I am with Truck Shop, there is nothing like the old Hendrickson suspension with the extended leaf, and top it off with the old 6 spoke wheels. I don't know if any of these young guys at the tire shop even know how to put a spoke wheel on straight anymore.
If you're wanting air ride just for a better ride I think you will be disappointed, they don't ride much better. The key to a better ride is air ride cab and a good seat. As far as air not holding up in off road conditions, never once had an issue or any trucks i've hired and i've hauled to some pretty rough dump sites, those air bags are tough as hell. Of the newer dump trucks around here i'd guess 75% are air ride at least. Guy who does all my trucking has 10 Kenworths all air ride no complaints at all. A big bonus to air ride is loading height, not a big deal if loading with big equipment, but if you are loading with small stuff it can be the difference between being able to load the truck or not. But unless that is a huge priority I don't think I would go with air ride, it's more things to go wrong. But if the truck was everything else you wanted for a good price, I wouldn't pass on a truck just because of air ride either. It's just every few years you might be dealing with a extra air leak. Only real concern could be if you plan to haul asphalt, got to keep it off the bags, but other then that they are tough as hell. Only thing I will say though, if you get spring suspension, make sure it's not on 24.5 rubber and/or a really tall box. Some genius at Western Star here was rigging light specs up with all 3, the side of the box height is just stupid, over 1' higher then most trucks, even with my 210 it's a nightmare to load them you can't see over the tailgate.
Mack Camel back, makes my back sore. I find a box with the connection points at the bottom of the chimney a lot more stable than a single point at the top like in the picture. Most of the full time dump trailer haulers say to make sure the load is in the center, so a good loader man is a must. Eyes on the gate, it only takes a second to make sure it's open. Watch your back wheels, you can tell when too much weight goes on them, or off them. If you are half way up, and she starts to go, floor it, putting it down won't always stop it, and chances are once the segments start to bend, it won't come down, and the inertia will take her over, gettin the weight off her is your best hope, and if it's stuck up top, she's going anyway. There must be truth to it, because I have only seen 2 upset in my life, and I have done the put her up, not down trick a few times myself.
So you're saying because a converted tractor on air ride isn't a good dump truck, air ride dump trucks are awful? There is a reason why they make different models of trucks, because they are made for different purposes and in no way is a tractor on air ride with a dump box thrown on the same as a factory purpose built dump truck on air ride.
Anyone who can lay a tandem dump truck on it's side air bags or not isn't smart enough to drive a smart a car, you can dump on a mean angle without a concern with air ride, IF it's an actual dump truck and properly built. In all my years of driving both types of suspension, never a concern of the truck going over, it's the concern of not wanting to dump on too much of a side slope because it's hard on everything, but the truck going over with a 15' box? Not going to happen.
A little grumpy are we?
The Hendrickson Extended leaf rides better empty at least. My problem with Hendrickson is the specialty tooling to change bushings. Camel back is expensive to work on, and the trunnion stand is the week link. I take Truckshop's suggestion for Hendrickson and raise him one to the Chalmers suspension.
The M2 Freight shakers they have been buying have whatever the he double hockey sticks this is for suspension. Rides ok loaded, but bouncy empty.
You ain't going to raise me nothing-chalmers is good suspension. Hendrickson beams are easy to remove.
A friend of mine had the press for changing the bushings in the truck which helped. The Hendrickson HX got rid of the bushings that require the press. The Chalmers suspension requires an air ride Cab in my opinion. I have the rare truck Mack Granite with Chalmers suspension. Loggers here swear by the Airliner suspension which comes in Freighliner and WesternStar, Not sure how it is dumping, but it works well in a 10 wheeler tanker. I was recently looking at a Kenworth triaxle dump truck until I saw the 8 bag kenworth suspension, NOPE!
I totally thought the same way. Never saw one but in the parts book is a Hendrickson walking beam set up with an air bag pivit in the middle of it. Chalmers and camel backs are tough. Have some of them around. Seeing more and more air rides in rough places. Some of them surprise me. Newer Petes are quite tough. I read that the Western Stars are the same. The KW 8 bag truck can drive circles around the Freightliners stuck in the mud and leave. Single axle air ride Mack spreader truck held up well. However in sugar sand it could wheel hop so bad forward movement was impossible. However in reverse it would go through the same place fine. The one in Truck Shops picture is hard to beat.
In loose/muddy ground the thing about walking beam is on uneven surface-one axle is always forcing the other axle down. I drove a 86 Pete dump with 46K extended leaf with front and rear lockers pulling a 3 axle pup, it was a great machine.
The Kenworth AG 400/460 8 bag is good suspension on a dump truck. My boss owns 8 dump trucks that mostly make their living in the woods building and maintaining logging roads year round. 1 is extended leaf Hendrickson, 2 are Chalmers and the rest are AG 460. Guess what trucks get used the most and which ones sit when we don't need them all running. The air ride when properly spec'd out on a proper dump truck is the way to go in my opinion. A converted light framed highway truck with some cheesy 4 bag suspension ain't gonna cut it in the long run. At the end of a long day it is the difference between going home and feeling like mowing the lawn or sitting in the recliner. As far as dumping while leaning that is something that simply takes experience to know what you can get away with depending on what you are hauling and where you are dumping and suspension makes very little difference in stability when you dump the air out of the bags. That is one thing you do want to do when dumping anyway mainly so you don't ruin the shocks and shock mounts when all the weight comes off the truck at once. When you're in a cold sweat with your heart in your throat you know you are gaining valuable unforgettable experience...
For something like that it's best just to take it to a shop who does them all the time, had them done years ago on first truck and it was mind blowing how cheap they are to replace, it wouldn't be worth anyone's time trying to do them themselves, the only thing the shop did was suspension and alignments. And I mean how often is it going to be done once maybe twice in the trucks lifetime?
Not at all and it wasn't directed at you, just don't like seeing people judging something based on someone half a$$ing something and saying "it didn't work so this is garbage". Converting a road tractor to a dump truck and saying it's awful means SFA towards what the OP was asking. Air bags have a purpose in dump trucks and have gotten so common for a reason.
The uneven dumping wouldn’t be my only concern about the air ride. Actually the main thing is getting in to spots. Backing up on fresh soft gravel when putting in new driveway, or over chunky bank run or shale. Off driveways into muddy grassy spots etc. I have a Volvo Triaxle now with double locking rears that I end up locking in frequently. the air ride setup that would be on the international truck I was considering is Hendrickson primax or HAS.
I always dump the suspension, but had only done it because I hate the bags snapping up like that all at once, I do the same when I drop a trailer or set the float on the ground to unload something. Never even thought of the shocks. Good point. I always compared KW 8 bag to driving on an icy road. Once you get used to it, it's fine, but the first time is strange.
I didn't figure you were mad at anyone in particular, you just seemed pi$$ed
I run one tandem 44k dump truck and one 21k CDL triple axle dump trailer. I also have a Diamond C 26k CDL 40' hydraulic dovetail trailer, and I spec'd it with Hutch suspension and 60" spread. Been doing this a few years now, actually started in France about 20 years ago with a Mercedes 2031 rolloff bin tipper. What you say above is true. I'll share what I've learned. 1) Yes a converted road chassis is suboptimal for a dump truck. But it's hard to find true dumps on the used market. The guys on job sites that I see get stuck, or who are down for repairs a lot, run converted Petes and Freightliners. The frames and suspension mount points don't seem to be as heavy. They also have no left-right axle locking, so we wind up pulling them out more often on job sites. They have front-rear axle lock, but that's it. If you pitch over a little due to uneven terrain or sink in on one side, the tires on the unweighted side both spin but the heavy side does nothing. A purpose-built dump should be able to lock all four drive wheels up. 2) Nobody out here in my area of Central Texas runs air bags. I see zero at the quarries except lift axles. I will admit that I haven't looked at all the new superdumps that are showing up around here closely. But a local quarry who delivers road base to my yard bought 8 and so far all that have come here have leaf springs. Each cost $350k btw. And forget about spare tires ... there three different sizes on those fancy superdumps! Sit and wait for the expensive truck tire guys is all you could do. But I digress. 3) I don't know if bags ride better or not, but on forums I've seen many posts saying no improvement. My F550 is bagged and raising the pressure certainly does not improve the ride one iota. It rides like heck. I think air bags are a gubbmint "suggestion" to reduce wear and tear on pavement. Like most gubbmint ideas, it's probably wrong. The unsprung mass in a heavy truck is only slightly diminished by bags if at all. Subtract part of the weight of leaf springs (the part attached to the hangers), add in all the weight of a bag system, and I bet it's mostly a wash. In France we pay a mileage tax and that tax is lower if your truck is bagged...maybe that why bags became popular in the first place. 4) I run about 15 trailer owners groups on Fakebook. Let me tell you about all the bitching we hear about bags on trailers. Perhaps bags on CDL trailers are less reliable than bags on Class 8 trucks. The trailer guys love 'em ... except when they don't work, which is too often if you ask me. I need my machines to be like anvils, so I can make money and not spend every weekend wrenching. FYI . .
If your truck is rough with air ride, it is a poor air ride, or it's not set up properly. I started my driving years in a Peterbilt, and never spilled my coffee. We run 3 tri axle dump trailers, 4 tandem dump trailers, and every float trailer that I have ever been around has been air ride. The discussion was had not long ago, and many a leaf spring has been changed, but it is very rare that a bag has been replaced. It's not the way I would do it, but our trailers run hard over rough roads 5 days a week, and they are loaded heavy. 27 metric tonne or around 30 old ton for the tandem trailers, and The guys with the tri axle trailers haul around 40 or 44 for you if they can get away with it. They supply material for our asphalt plant, and materials for pipe work, and road building. Besides freezing up sometimes in fall, no issues. The wood haulers are all air ride as well, and they go off road a lot more than we do. I'm not crapping on the traditional suspension, but there is nothing wrong with air ride. It's like automatic transmissions. They are getting a lot better, and becoming more common. We have 2 identical Freight Shakers, 2 years apart. Same configuration, suspension, engine, rears. One is a 2019, and the auto is a 21. The 21 is almost 300Kgs lighter, and from what I have seen, gets lower fuel consumption.
Give me walking beam on a dump truck every time. We use our tandem more off-road than on-road so the Hendrickson walking beam is almost fool proof. Could care less how it rides down the road empty. All the tri-axles here run walking beam type suspension, there may be an odd ball converted road tractor on air but it's rare. Tri-axles can legally haul 25 tons on state and secondary roads here so the dump truck companies know what works best for them. We don't see concrete trucks on air-ride here either.
After thinking about it for a day or two, that truck is long gone anyway.
Never realized suspension was such a hot topic....
I know, good thing there are lots of options, something for everyone.
Don't start a gas vs diesel HD pickup thread...yikes!
It's just Firestone bags over std leaf suspension. I mainly use it for a little more ride height when hauling the 40' dovetail. Canada seems to be much different from Texas in suspension choices.
I currently have (2) dump trucks. My first ('94 Pete 377) is a converted OTR truck with Peterbilt AirLeaf. The frame was extended (so it is stiffer due to overlap across the splice) and the dump bed has a subframe. As you can imagine there is just not enough frame flexibility to keep traction when the ground requires articulation of the suspension. Loaded is no problem. Empty requires due diligence to not get stuck. It rides great down the road when empty. When loaded the air bag suspension allows more side to side sway so one must get used to that. The other truck ('84 KW w900) has the extended leaf walking beam. In my opinion it is a great suspension when driving over rough/off-road terrain. It gets traction regardless of empty or loaded. In my area I have seen many dump trucks (converted from OTR trucks) that employ the KW 8-bag air ride suspension. I don't know enough to be able to identify if they are AG400, 460, or what, but they do seem to get much better traction than my Pete AirLeaf does. I think that the extended leaf walking beam is a great dump truck suspension. It's been proven over the years as well. I suppose the bushing tool can be an issue for some but there are all kinds of services available for getting this done. Many will come to you. Sorry, I just don't quite agree with the better ride comment....Maybe when compared to Hendrickson pad. In my opinion the empty ride quality is one of the drawbacks (on the driver and the truck). Air ride cab goes a long way to remedy this. Comparing the ride quality of a spring suspension system (like that of an F550) that is supplemented with air bags, to a true air bag suspension is not quite "apples to apples". Adding air to your F550 bags will only serve to make it stiffer and, no matter how much, or little, air you have in those bags, it will never be softer than the springs.
The Hendrickson Extended leaf is different then the standard hendrickson, the top leaf is longer, so when empty you only ride on the one longer leaf rather than the standard hendrickson where you ride on the entire spring pack all the time. So load carrying capacity when loaded, smoother ride when empty.
Does that Pete have locking axles, or just front/rear interlock? That's all my IH dump has, and so far I've never gotten stuck. But I've seen other guys get pitched to the side a bit, then the light side just spins while the heavy side does nothing. They have to lower the bed and wait for a machine to come pull them out. It's embarrassing. Yeah, comparing added bags on leafs to full air is not worth much. I've never been in a full bag truck except the one I took driving classes in, and that was years ago.
My Peterbilt has a diff-lock, but not full lockers.
Hendrickson INTRAX and is also on Western Star I drive. Is a little icky feeling when started driving it as will side roll something fierce in corners with heavier loads. Light Weight was the selling point and as such I am not much of a believer in it other than Low Maintenance. Still will get stuck, truck has Power Divider and Lockers but once starts down will not recover. Shop I run out of runs many tubs and air ride tractors, dump the suspension and dump the load except Off Level has still done in a few.
just get a rhinestone and stud kidney belt.
Must be a really different air ride. I have never seen a strait truck upset dumping a load. Another company I worked for when I first got into road work, I ran a real dump truck, camel back suspension bulldog on front. We had to haul along side of the wiggle wagons. I have dumped laying over so hard that the box wouldn't come down until you moved forward and leveled up. There were a few old converted tractors that hauled with us. They were owner operators, so they were a bit more careful, but same conditions. They run that intrax on our tandem/tandem and that little rubber block on top tends to lay over after a while.
A Few things of INTRAX, NEVER EVER Raise the bed with Drop axles Down, all the weight needs to be On the Suspension. If on unlevel raise only enough to get material moving, back up and tag brakes to shift more to back of box, if STICKY spray the bed nose area with Diesel before load.
Yeah what I have in the picture is not Intrax. Still don't know what it is. It's a rubber block over spring combo Didn't realize Hendrickson had their own air ride. Not popular around here.
Never seen here. Our strait trucks don't run air lifts unless it was a single axle with a tag, and they went away with gas jobs. Tandem, tri drive or twin steer. I never even heard tell of a super dump until on here. I can honestly say I have never seen a strait dump truck go over while dumping. Hoping I don't jinx some poor driver this season. Seen a few connections fail, and boxes come strait down and put a back window out.
Never seen a straight truck on it's side either, it takes a special kind of stupid to do so, the only way any driver not completely incompetent could lay one over is if the ground gave away on one side. I have dumped with air ride as well as hendrickson on some sketchy side slopes and never worried about it going over. With a 15'-16' box it's not that high up. The one's who could lay a straight truck over are the same one's who end up in the ditch on a clear day in the middle of summer. Only other way it could happen is a really stuck load or tailgate not open, bad side slope, and really jerky motion going ahead trying to get it to dump, but again if the driver isn't completely incompetent it will never go over.
Its always a bad deal. But sometimes things don't work out and locations aren't always what they should be. And you should know better than to jinx your driver- "nothing like that happens here" Nah- that just means you've never been anywhere sketchy. I've drug a lot of equipment around with dozers and excavators, and then you talk to some of the pipeline boys, or the guys building ski slope lift towers, or powerline guys- and they've got three dozers anchoring off stuff on the side of a mountain. Just because you've never been in a spot to roll a dump truck, doesn't mean those places don't exist. Lots of places here where you can lose a concrete truck or a dump truck with the bed down, let alone dumping. I might think I've got it bad when I get a set of tandems showing a little daylight- or when the steer tire comes off the ground coming out of a hole, but those boys in the backwoods would scoff at what I think is a bad spot. Mud is the same sort of thing- I think its a pain when I have to get a dozer or a excavator, or my old winch truck to get equipment moved around on a site, but then you watch on youtube some siberian river crossing where they are driving through mud up to their windows, and I've got it pretty easy.
Sketchy, steep, heavy and steam rolling.
Yeah- those logger boys having big water tanks, and lines to the drums to keep the brakes cool is a whole different world.
I have seen a few dump trucks on their side that had experienced drivers. Put the box up with things level enough, one side settles enough that the box is bound up and won't go down and the load (usually mud) is stuck at the front, try to pull ahead, whammo. Never say never. I have never rolled one but have scared myself a few times. It makes no difference what suspension is in it either at that point, with the bags dumped air ride is just as stable as walking beams.
I would disagree, i've dumped in some really sketchy places, but if you take proper precautions it's pretty much impossible to tip over a tandem without a sinkhole or something underneath. If it's really soft I might only put the box up 1/2 way up, get even 1/2 load out, then all way up for the rest. And you have to be on the ball to put the box down if one side starts going down. It also depends on the loads, if i'm hauling sticky clay i'm not dumping on a crazy side slope, but if it's something like black dirt that is light and you know it's coming out not worried about it. I'm more careful then most, considering it's my truck and my $$ if something breaks. Now a end dump is a different story, the first time I hauled one was garbage and it jammed in the tailgate, I almost sh*t myself unloading that because a 30' box all the way up sways like a SOB. But even those, it's rare to see one on it's side.