Bouncing Problemos

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Re: Bouncing Problemos

Post by Reloaderguy » Mon Nov 05, 2018 12:35 pm

The initial swaying feeling is a combination of slack in the Smart Bar, low rebound dampening, short rear sway bar, inboard rear coils, and weight high up on the chassis. Lower tire pressure helps absorb some of it. Start with a set of Airlift ultimate airbags in Daystar cradles run at 5 to 10 psi all the time. The airbags are mount outboard of the coil springs and support the chassis as the body starts to roll. A Thuren rear trackbar will sort out the rear wiggle you feel in off camber, sweeping turns.

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Re: Bouncing Problemos

Post by DamageWagon » Tue Nov 06, 2018 12:22 am

I still have yet to figure out why some trackbar bushings wear out so fast. I think almost every early death one was from Moab, minus two exceptions I think, which makes sense with all the chassis movement, dry steering, potentially heat saturation.

But then my truck has been like Lee’s I’m averaging 30,000 miles on a bushing set and both of us drive more like monkeys in the dirt. Guys with radius arms are somehow wearing out bushings faster on some occasion even though their axle produces forces they are much nicer on the trackbar than the 03-13 trucks with the short arms.

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Re: Bouncing Problemos

Post by olyelr » Tue Nov 06, 2018 6:59 am

DamageWagon wrote:
Tue Nov 06, 2018 12:22 am
I still have yet to figure out why some trackbar bushings wear out so fast. I think almost every early death one was from Moab, minus two exceptions I think, which makes sense with all the chassis movement, dry steering, potentially heat saturation.

But then my truck has been like Lee’s I’m averaging 30,000 miles on a bushing set and both of us drive more like monkeys in the dirt. Guys with radius arms are somehow wearing out bushings faster on some occasion even though their axle produces forces they are much nicer on the trackbar than the 03-13 trucks with the short arms.
Would a track bar bolt that is not properly torqued down cause premature wear to the bushing? Im sure that happens all the time.
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Re: Bouncing Problemos

Post by 2wagons1driveway » Tue Nov 06, 2018 8:12 am

Yes that would for sure. Same with having too much angle difference between the frame side bushing and the axle side (constantly tweaking the frame side bushing) the radius arm trucks I imagine, given their swing of the axle, wear the track bar bushings faster compared to the four link/ fine link trucks front ends. Still though seems pretty crazy they wore out that fast. I thought that stuff only happened to carli bars Lolol


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Re: Bouncing Problemos

Post by OffroadTreks » Tue Nov 06, 2018 12:22 pm

DamageWagon wrote:
Tue Nov 06, 2018 12:22 am
I still have yet to figure out why some trackbar bushings wear out so fast. I think almost every early death one was from Moab, minus two exceptions I think, which makes sense with all the chassis movement, dry steering, potentially heat saturation.
We measured them in Moab again, they never climbed above 80 degrees. It is not heat. Three non-Moab exceptions, Mine, Mike, David all had failures outside of Moab. Then David and I had repeat failures again in Moab.

Worse, the failures not in Moab were tame in comparison. No real crawling on Ouray for me. Mike B said he was doing tame CO trails, and same with David.
2wagons1driveway wrote:
Tue Nov 06, 2018 8:12 am
Yes that would for sure. Same with having too much angle difference between the frame side bushing and the axle side (constantly tweaking the frame side bushing) the radius arm trucks I imagine, given their swing of the axle, wear the track bar bushings faster compared to the four link/ fine link trucks front ends. Still though seems pretty crazy they wore out that fast. I thought that stuff only happened to carli bars Lolol ImageImage
That's the running theory that Neil has, and I think he might be right. Thuren doesn't think so, but the strikes against him for "I never actually tested it on a PW are 3 to 0". We've all verified torque spec.

On these past two failures I had, the bushing itself remained in tack, but the center ovaled out. Think David reported the same thing.

What would cause them to repeatedly oval? Thinking there is some extra movement with the articulink.

I'm on my 4th set of bushings now.
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Re: Bouncing Problemos

Post by DamageWagon » Tue Nov 06, 2018 12:31 pm

olyelr wrote:
DamageWagon wrote:
Tue Nov 06, 2018 12:22 am
I still have yet to figure out why some trackbar bushings wear out so fast. I think almost every early death one was from Moab, minus two exceptions I think, which makes sense with all the chassis movement, dry steering, potentially heat saturation.

But then my truck has been like Lee’s I’m averaging 30,000 miles on a bushing set and both of us drive more like monkeys in the dirt. Guys with radius arms are somehow wearing out bushings faster on some occasion even though their axle produces forces they are much nicer on the trackbar than the 03-13 trucks with the short arms.
Would a track bar bolt that is not properly torqued down cause premature wear to the bushing? Im sure that happens all the time.
That is the cause of almost every short-lived bushing, yes. Not torquing to spec is a big problem. You also have to re-torque after you’ve broken in a new bushing.

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Re: Bouncing Problemos

Post by Reloaderguy » Tue Nov 06, 2018 1:10 pm

The OP doesn't have a trackbar problem.

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Re: Bouncing Problemos

Post by DamageWagon » Tue Nov 06, 2018 1:24 pm

What’s a good thread without a responsible derailment?

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Re: Bouncing Problemos

Post by 1pieceatatime » Tue Nov 06, 2018 2:25 pm

I'm appreciating the dialog, as it's informative and I am not sure exactly what my main issue is yet! Lots of advice here to sort through for my specific issue.

It may be better in a dedicated thread with an appropriate title though - may help other folks find it via search for future reference.

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Bouncing Problemos

Post by 2wagons1driveway » Tue Nov 06, 2018 3:27 pm

De-rail continues: All I know is mines had a hard life, and it’s lived long and tight- I’m honestly surprised the radius arm trucks are eating them up maybe don needs to do some more research into how the power wagon specific failures are occurring I know he loves a good challenge. As always be sure to give him feedback with whatever you find because it does sound like this is something that only concerns us p.wagon guys and more specifically the radius arm trucks.

Me personally I have always upped the torque specs on the fourth gen bolts even by 20-40ft lbs... or much more- pretty much as tight as I can get those things.

To totally rule out that these bushings have all been torqued enough we should be checking inside the track bar bracket for any signs of the actual bushing sleeve moving as that would indicate inadequate holding torque. And given all 7000 plus lbs of force on these things even during a small crawl in Moab when the trucks virtually sideways most trails I’m sure that could eat the bushing up mighty quick.

Last time I chatted with don or even carli guys about track bar frame side bushing failures it seemed to be a common issue for them to fail if they weren’t torqued properly or the rod end was being torqued in a way that when axle fully drooped it would put a ton of load on the bushing in a way it wasn’t designed to handle load (twisting forces)

Something to consider.

But back on track: did the OP fix their problem yet or whaaaaaa?


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Re: Bouncing Problemos

Post by Reloaderguy » Tue Nov 06, 2018 3:38 pm

1pieceatatime wrote:
Tue Nov 06, 2018 2:25 pm
I'm appreciating the dialog, as it's informative and I am not sure exactly what my main issue is yet! Lots of advice here to sort through for my specific issue.

It may be better in a dedicated thread with an appropriate title though - may help other folks find it via search for future reference.
I addressed it at the top of page 2. You need airbags or custom valved shocks with the a lot of rebound dampening.

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Re: Bouncing Problemos

Post by OffroadTreks » Tue Nov 06, 2018 4:05 pm

Reloaderguy wrote:
Tue Nov 06, 2018 3:38 pm
I addressed it at the top of page 2. You need airbags or custom valved shocks with the a lot of rebound dampening.
This is based on your assumption that his problem is simply the weight up high. I had the SAME experience with a bad fornt track bar. Once the bushing was replaced, that's never happened again. SAME EXACT experience he described, with the sway and the sway control kicking in.

I say check the track bar.

If it's solid, then move to those steps. Really, we already explained how to check the trackbar.

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Re: Bouncing Problemos

Post by RustyPW » Tue Nov 06, 2018 5:59 pm

DamageWagon wrote:
Tue Nov 06, 2018 1:24 pm
What’s a good thread without a responsible derailment?
:lol:

My first track bar was a 1st Gen Carli. After a couple of bushings. I decided to get another bar. Looking at the 2nd Gen Carli and the Thuren bar. The Thuren bar was the same design as the 1st Gen Carli bar, only with different poly bushing. I figured that it will fail too at some time. So I went with the 2nd Gen Carli bar. Different design on the frame mount bushing. So far, so good.
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Re: Bouncing Problemos

Post by 1pieceatatime » Sat Dec 01, 2018 7:29 pm

So I talked to Carli, Thuren, Pure Performance, and AEV yesterday. In short, the consensus was I need more rear rebound damping and reduced rear roll via a stiffer rear roll bar and raised rear roll center.

Here is a longer summary of the conversations:

Pure Performance, Carli, and Thuren setups all lift the truck and use softer springs and shocks, which would make the problem worse. All of them said something along the lines of “don’t use our stuff - it would not be the right compromise for your setup”. They specialize in super-compliant rock crawling or high-speed desert bombing. I’m not after either - I want to maintain OEM Power Wagon level off road capability while carrying our camping setup.

AEV’s suspension lifts the truck, but swaps to stiffer springs (normal 2500 springs as opposed to Power Wagon) and stiffer shocks, and also raises the rear roll center several inches by relocating the rear axle track bar mounting point, which helps keep the truck flatter when cornering. They were confident their suspension would help because they have run roof top tents fairly high up on their shop trucks, but IMO it’s not clear that it would solve the problem given raising the truck works against me while the spring/shocks and track bar geometry will help but probably not eliminate the issue.

Carli, Thuren, and Pure Performance all told me to buy a Hellwig rear sway bar, as it is stiffer than what they offer and will help keep the rear roll under control. Downside is less compliance off-road, but if I really needed articulation I guess I’d be disconnecting it anyway.

Carli and Pure Performance suggested looking into the stiffer, adjustable range of Fox shocks so that I can stiffen them when loaded up for a trip and soften them when commuting or off-roading. Downside is probably a little harsher ride on and off road. Thuren and Pure Performance told me they could build me shocks with custom rebound valving that could help if I really wanted them too, but they didn’t think it would eliminate the issue and suggested I consider that approach as a last resort since I wouldn’t likely run their softer springs.

AEV and Pure Performance said to raise the rear roll center, although Pure Performance didn’t have a suggestion on how to accomplish this, and it appears I would have to buy the whole AEV suspension to get their rear track bar axle mount relocation kit.

Carli and Thuren said they don’t think that the front/rear track bars are causing the problem, but both suggest upgrading them when OEM ends wear out for more direct steering feel.

They all pretty much told me that this behavior comes with the territory given that much weight carried way up high - it can surely be improved but probably not eliminated.

I appreciate the air-lift bag advice received here, it’s an option still but in discussing it with Thuren and Carli, they pointed out that my issue isn’t really specifically spring rate although it could help - but it will also stiffen the rear ride and probably is a worse compromise than sway bar and shocks. The sway bar is a spring too, but only operating in roll - exactly where I need it in this case.

So... more research to do over the winter, as I’ll wait until after the Michigan salt and snow to put shiny new parts under the truck. Looks like I’ll more or less have to decide between upgrading to AEV’s suspension - or piecemealing a Hellwig rear sway and Fox adjustable shocks. At this point I’ll meaning toward the latter because I wasn’t really planning to go to 37” tires and a re-gear that would likely piggy-back on the AEV setup.

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Bouncing Problemos

Post by DamageWagon » Sat Dec 01, 2018 8:15 pm

Those answers are on track but they don’t sound quite right with your issue. Did you talk with Chris at Thuren?

Raising the rear roll center is a big deal in a good way... why the solution wasn’t proposed by any of the vendors is totally beyond me (I imagine Thuren did mention their rear trackbar kit that does exactly what every vendor said needs to be done?). Thuren makes an outstanding solution to raising rear roll center and nobody else in the industry has even bothered to get out of bed and try to hold a candle to that product. 100% do it, there are only good things to come of it.

The point of air bags is not to do with spring rate, it is to do with spring spacing. The coil springs in the rears of these trucks sit very narrowly, the point of air bags is to provide a better spacing.

You have options with rear springs. A better spacing (air bags) will do a lot more than spring rate will. By adding spacers into the options you can play with height as well as spring rate, though you don’t really want to go beyond a 1.5” spacer in the rear.

Better shocks are always a big improvement, but shocks should always be done after you’ve done everything you can to improve the system - geometries & layout, then spring rate, then shocks.

Thuren will definitely build you shocks valved specifically to help with your issue and to run with your stock springs. You don’t need to swap springs.

Beware anyone trying to sell you shocks with clickers/adjusters as a solution to any problem. Adjusters don’t make that much difference on heavy vehicles and are only for narrowing things in, they are not the big change that the base valving is. The exception to this is Bypass tubes, which are a completely different thing. But that you cannot run anyways.

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Re: Bouncing Problemos

Post by 1pieceatatime » Sat Dec 01, 2018 8:50 pm

It was Chris at Thuren. In our discussion I don’t recall him mentioning their rear track bar kit - in my notes the rear roll center height came up in talking to AEV and PP - but perhaps he did say something and I missed it. At any rate I just checked out Thuren site and that looks like it is just what the doctor ordered! Good call, thank you.

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Re: Bouncing Problemos

Post by OffroadTreks » Sat Dec 01, 2018 11:41 pm

1pieceatatime wrote:
Sat Dec 01, 2018 7:29 pm

So... more research to do over the winter, as I’ll wait until after the Michigan salt and snow to put shiny new parts under the truck. Looks like I’ll more or less have to decide between upgrading to AEV’s suspension - or piecemealing a Hellwig rear sway and Fox adjustable shocks. At this point I’ll meaning toward the latter because I wasn’t really planning to go to 37” tires and a re-gear that would likely piggy-back on the AEV setup.
DO NOT UPGRADE TO AEV, It's a downgrade. You do not need their suspension. You will end up with a leveled truck and throwing away half of your parts. The AEV kit is designed around diesel owners. There are lots of threads here about it. Just do not waste you money there, please.
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Re: Bouncing Problemos

Post by Oilbrnr » Sun Dec 02, 2018 12:07 am

Tires.

I've been experiencing the same wallow as the OP for several months now after adding additional weight to my '16. Between the shell, rack, solar, 2nd battery, compressor, bumper, recovery gear, fridge, awning, tools and a partridge in a pear tree, I'm at 9,125 without food, water or extra fuel. 451 of that is above the bedrail. My hand calculations were verified by a Cat scale.

Off came the 35x12.50 Durapads this week and on went General X3s. Wallow gone. 45k on the clock. Stock suspension, for the moment.

And, for the record, I like KO2's but I know that we, Discount Tire, were seeing premature wear on trucks such as ours that are, umm, rather portly. Not sure if Michelin has sorted out their compound or not yet (that winter traction does come at a price) but I'll find out.
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Re: Bouncing Problemos

Post by Reloaderguy » Sun Dec 02, 2018 1:16 pm

I addressed your issue at the very top of the page, you need more spring rate in the rear. You can start throwing money at the issue or you can take the advice of someone who has already experienced what you're going through. The AEV lift may actually solve your problem but not because of the BS line they laid on you. AEV wants you to install standard 2500 rear springs which will give you more spring rate, ie more resistance to roll. The problem is then you have to live with the junky, unsafe AEV lift. Hellwig's swaybar is total overkill for your weight and your ride would be awful. Or, you can buy a set of airbags and cradles and be done with it. Your choice.

FYI, The 14+ PW has a lighter rear swaybar than a standard 2500. If you really wanted a heavier swaybar you could buy an OE bar for less than $100.

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Re: Bouncing Problemos

Post by olyelr » Sun Dec 02, 2018 2:51 pm

You should try something like installing regular ram rear coils with a spacer to get it back to level, regular ram rear sway bar, and thurens rear track bar. I think that would help a ton for your intended use. Would you loose some rear articulation, well of course, but you gotta loose some to win some.
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Re: Bouncing Problemos

Post by DamageWagon » Sun Dec 02, 2018 2:55 pm

I think regular 2500 springs are a poor compromise. They are stiffer but the geometry is still poor, a wider spring base will have a far greater effect than a small spring rate increase. Air bags are going to do a lot more, even if they are at a low pressure, just by providing a much wider base for stability.

The stock spring layout is so narrow, a lot of he motion you get is from the chassis pivoting on the springs like a seesaw.

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Re: Bouncing Problemos

Post by olyelr » Sun Dec 02, 2018 4:28 pm

DamageWagon wrote:
Sun Dec 02, 2018 2:55 pm
I think regular 2500 springs are a poor compromise. They are stiffer but the geometry is still poor, a wider spring base will have a far greater effect than a small spring rate increase. Air bags are going to do a lot more, even if they are at a low pressure, just by providing a much wider base for stability.

The stock spring layout is so narrow, a lot of he motion you get is from the chassis pivoting on the springs like a seesaw.
So then in reality, having bags added (with factory springs) should greatly improve drivability with the added weight in the back, yet still offer the off roadability of the factory setup (for the most part).

So bags and a thuren track bar for the win :mrgreen:
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Re: Bouncing Problemos

Post by Reloaderguy » Sun Dec 02, 2018 4:51 pm

olyelr wrote:
Sun Dec 02, 2018 4:28 pm
DamageWagon wrote:
Sun Dec 02, 2018 2:55 pm
I think regular 2500 springs are a poor compromise. They are stiffer but the geometry is still poor, a wider spring base will have a far greater effect than a small spring rate increase. Air bags are going to do a lot more, even if they are at a low pressure, just by providing a much wider base for stability.

The stock spring layout is so narrow, a lot of he motion you get is from the chassis pivoting on the springs like a seesaw.
So then in reality, having bags added (with factory springs) should greatly improve drivability with the added weight in the back, yet still offer the off roadability of the factory setup (for the most part).

So bags and a thuren track bar for the win :mrgreen:
I worked with Don on rebound dampening in his Kings for this very reason. He used my truck to develop valving specifically for trucks with caps or RTT's. Airbags were the solution. I have every part Don makes for 4th gen trucks on my truck, most of which are preproduction. Again, the issue is inboard mounted coil springs, slack in the swaybar, and a short trackbar with excessive angle. Airbags stop the sway.

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Re: Bouncing Problemos

Post by 1pieceatatime » Tue Dec 04, 2018 1:28 pm

Regarding airbags -

Please bear with me as I try to understand the pros/cons. I am not trying to be an argumentative ass, nor am I trying to disregard the hard-won experience of others - I really appreciate the help and am simply seeking to better understand.

What sort of airbag setup is recommended? Looking around online, it seems there are airbags that are attached both to frame and axle, airbags that sit on axle, and airbags that attach to frame. Perhaps a link to what I need will help answer some of my questions.

My understanding is that the "traditional" use of air bags on the rear of a pickup truck is to add load capacity by increasing rear spring rate. I don't really need that, as I am not overloading the rear springs with weight - I'm well under max payload, I'm not squatting the rear too much - I just have too much weight up high for OEM suspension. But if I understand correctly, the suggestion here is that there is a geometric issue with the rear coils in this suspension being too far inboard, and acting almost like a pivot point for the body/frame of the truck to rotate on in roll... if that is the case, I could resist this roll by adding stiffer rear coil springs, which would have a negative side effect of a harsher ride. I could also add rear air bags spaced wider apart than my coil springs, which would also increase the effective rear spring rate, causing a harsher ride but less roll - just like stiffer coil springs. Is the logic here that because the airbags are spaced wider apart, I can add less overall rear spring rate to get the same anti-roll effect due to geometry? And doing this would cause less of a compromise for rear ride?

Assuming I understand all that correctly, it brings me back to the question that if I don't really want stiffer rear springs for general ride / up-down suspension movement, but I want to reduce rear roll, why is an airbag setup - which impacts ride as well as roll - better than a stiffer rear sway (anti-roll) bar, which does not negatively impact ride but will limit roll?

Again - these questions are submitted respectfully for your consideration, not trying to pick fights - just trying to get my own head straight and learn.

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Re: Bouncing Problemos

Post by DamageWagon » Tue Dec 04, 2018 1:40 pm

Correct, the point of the air bags is not so much spring rate but rather just a better spacing of the springs to prevent roll. The AirLift style with Daystar cradles on the axle is a great setup as it allows the axle to droop out from under the bag during articulation, and the AirLift bags with the internal jounce stop can be run with 0 air in them (unlike most bags). Like you said, you don’t need to add much air because it isn’t there for load capacity. Running ~10psi in the bags would help a lot with handling but have a minimal impact on ride quality, especially since there’s some weight on them at all times and they’re at the back of the truck.

A stiffer rear swaybar would also help but has larger compromises when it comes to articulation. The rear swaybar on these trucks suffers a similar downfall as the springs, in that the mounting is fairly narrow inside the frame. A better solution is what one of the Moab guys did, adding a Currie Anti-Rock swaybar that mounts outside the frame - he had a very good improvement from that, but that is custom fab.

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