Bouncing Problemos

[1pieceatatime]

Long post, but I figured I'd get everything out there I could think of right off the bat...

2018 PW with following mods:
- 35" K02 on AEV wheels
- JB roof top tent on Nuthouse Rack, ~230lbs total
- Coiling bed cover, ~50lbs?
- Spare Tire deck (above bed rails) and spare tire, ~150lbs?

I typically run tires ~60psi all the way around. New truck, so hadn't experimented much from where it was when I drove it off the lot. More on tire pressure in a bit.

We took our first big trip with this new rig fully-loaded, total from above ~430lbs and another ~400 in gear and family of 3 at 380, so call it about 1200lbs. On the way out West did not really notice any strange behavior - could tell the truck was heavy, but no real degradation in performance.

We did a multi-day off-road trip, I had dropped tire pressure to 20psi, locked diffs, and disconnected front bar. When we went back to highway, I aired up but decided to try 45psi front/rear instead of my normal ~60 to see if it improved the ride. Wasn't on highway for too long before we ended up doing ~40 miles out and back on some pretty rough washboard roads at 30-40 mph, still at 45psi.

Now back to highway driving and the trouble starts. The truck started to oscillate side to side in roll when at highway speed, moderate cornering. Primarily at turn-in or straightening out from turn - if it was a long, sweeping turn, the truck would settle into the turn after several seconds of oscillation. Sometimes if there was a bump in the corner, it would do it worse. Oscillation takes several seconds to subside.

At least twice the oscillations got so bad that the nannies kicked in and cut engine power, which freaked the hell out of wifey and little guy as it happened in a turn on the highway!

Given it is a bounce and happening in transient cornering conditions, my first thought went to a broken shock. There are no outward/visible signs of this - no oil, nothing bent/dented/broken that I can see. Perhaps the stock shocks just aren't capable of handling the increased weight/CG of my setup?

Next I though maybe the smart bar wasn't reconnected or was reconnected with preload / not straight. There is no misalignment and the light is not on, so the easy stuff is checked - but how do you actually know the bar is locked/connected?

Perhaps the tire pressure is too low now, and I'm getting uncontrolled sidewall movement?

The truck is back to "unloaded" state, which means the rack/tent/cover are still on but all the gear is out of bed and the spare, spare shelf are off. The behavior is much more muted, but it is still there. Certainly reduced enough that I don't think I could make the nannies come on if I tried, but in certain cornering conditions - especially a bump in the middle of a turn while cornering moderately at highway speeds - the truck is definitely still bouncing side-to-side in roll, behaving differently than it did pre-trip.

Anybody else ever run into something like this before? Any ideas on what to try next? I was thinking of going back to 60-65 psi in the tires, but every post I read on here would tell me that is way too much for my truck.

[OffroadTreks]

Now back to highway driving and the trouble starts. The truck started to oscillate side to side in roll when at highway speed, moderate cornering. Primarily at turn-in or straightening out from turn - if it was a long, sweeping turn, the truck would settle into the turn after several seconds of oscillation. Sometimes if there was a bump in the corner, it would do it worse. Oscillation takes several seconds to subside.

At least twice the oscillations got so bad that the nannies kicked in and cut engine power, which freaked the hell out of wifey and little guy as it happened in a turn on the highway!

Anybody else ever run into something like this before? Any ideas on what to try next? I was thinking of going back to 60-65 psi in the tires, but every post I read on here would tell me that is way too much for my truck.

Id bet money your front track bar has gone bad. How do I know? I have a very very similar setup, and experienced THE SAME THING returning from Colorado recently.



I got the oscillation side to side on the highway. The nannies are actually the trucks anti-sway control kicking in.

My trackbar bushing on the frame side was bad. I'd bet money yours is too. Had no problems till the end of our trip. Likely got tore up on the trails.

Thuren says the stocker is good to about 20k miles before it’s worn and then if you actually use your Wagon... yeah.

I've got a better setup in terms of shocks, tires and lower deck height on my tent, and it still happened.

Start there.

Another thing, you should drive over the cat scales with your setup so you get an idea of how much weight is actually on each axle. My tire pressures are usually more in the front than the rear, because I have more weight up front than out back, despite our gear. Weight with the family in the truck so you have your true on road numbers.

And then you can chalk test your tires to find good pressures.

[DamageWagon]

That weight up so high is going to be a major contributor. I always try to keep weight like that down low, going above cab is murder.

That distance over washboard roads at that speed, it is very possible that you either smoked your shocks or temporarily overheated them. Did this behavior continue after the shocks had time to cool? On stock shocks, even on road, if you are continuously swaying the shocks are moving through their stroke and will heat up AND mix the nitrogen with the oil which makes hem almost useless. How does the truck do after it has sat for a while?

Are you on stock suspension otherwise, stock trackbar front and rear? How many miles on your truck?

[OffroadTreks]

Yeah does have a ton of weight up in the air. Same problems Aaron had with his setup. We have a friend, who was running a similar RTT hardshell on top of his truck cap and just had poor handling and what not. When he got rid of the cap and brought it all down and lowered his COG handling improved significantly. You've got almost 100lbs of tire floating above the bed and then a giant counterweight floating over the roof.

I can't imagine you have enough balance weight in the bed itself.....

You could always add air bags to your rear coils, make them stiffer.

[1pieceatatime]

What's the best way to validate that the track bar bushing is good or bad? Visible damage? Excessive play in a specific direction?

[OffroadTreks]

What's the best way to validate that the track bar bushing is good or bad? Visible damage? Excessive play in a specific direction?

I'm terrible at explaining it, maybe DamageWagon or someone else here can break it down.

It can be done with a helper in your driveway. Sometimes there is no visible damage. I had a bushing oval out and if you just looked at it, it looked fine.

Sorry I'm not more help.

BTW, you need an intro thread, looks like you have a nice setup there.

[RustyPW]

Sounds like a trackbar bushing. Had a couple of them go bad on me.

To check the frame mounted trackbar bushing. Have someone in the truck. You laying on the ground, looking at the bushing. Have the person in the truck start the truck up. Then have them turn the steering wheel to the left, then to the right a couple of times. If you see movement. It's bad. Do the the same for the axle mounted bushing too. While you are doing this. Might as well look at the rest of the tie-rod joints too.

If it's bad. you have two choices for replacements. The Thuren or Carli trackbars. Both are adjustable to center the axle under the truck. The Carli bar does away with the poly bushing on the frame end.

[OffroadTreks]

BTW, I meant to say I have a more "advanced" setup, not "better". Didn't want to come off saying I'm better than you. And re-reading it sorta sounds like that. Sorry if it came off that way.



I just meant I'm already running aftermarket front and rear trackbars, King 2.5 shocks which are twice the size of the stockers, aftermarket coils, larger tires, and have a lower COG, etc, etc and still had a track bar bushing fail. Which is what lead me to my conclusion.

[RustyPW]

BTW, I meant to say I have a more "advanced" setup, not "better". Didn't want to come off saying I'm better than you. And re-reading it sorta sounds like that. Sorry.

I just meant I'm already running aftermarket front and rear trackbars, King 2.5 shocks which are twice the size of the stockers, aftermarket coils, larger tires, and have a lower COG, etc, etc and still had a track bar bushing fail. Which is what lead me to my conclusion.

You always say you're better then everyone else.

[OffroadTreks]

BTW, I meant to say I have a more "advanced" setup, not "better". Didn't want to come off saying I'm better than you. And re-reading it sorta sounds like that. Sorry.

I just meant I'm already running aftermarket front and rear trackbars, King 2.5 shocks which are twice the size of the stockers, aftermarket coils, larger tires, and have a lower COG, etc, etc and still had a track bar bushing fail. Which is what lead me to my conclusion.

You always say you're better then everyone else.

Well, I mean Michael is from the Hebrew name מִיכָאֵל (Mikha'el) meaning "who is like God".










I took a personality test once and well, I haven't chopped anyone up, so that's a good thing.

[1pieceatatime]

Thanks for the help, fellas. I get the comments about the advanced suspension, no offense taken.

A few answers to questions I read above:

- Picked up the truck mid-June, 18k so far

- Suspension currently stock

- 35" K02 (which I have nothing but good things to say about - so far, anyway)

- Behavior is still there, although much reduced. I have the truck back to "commuter" with the rack/tent still on but the spare tire and tire shelf removed. Shortly I'll probably take the tent off, as we don't plan to use it in the winter and no need to subject it to Michigan weather for the next 4-5 months...

I'll check out the track bar bushing this weekend when the rain dries up.

I'll post an intro thread.

[verdesardog]

60pis tire pressure? Get your truck weighed (front and rear seperatly) and set the tire perssure according to the load table for your tires. I have 315/70/17 on my Dodge diesel and run 35 front 32 rear,no bouncing, very nice ride for a 3/4 ton truck!

[RustyPW]

60pis tire pressure? Get your truck weighed (front and rear seperatly) and set the tire perssure according to the load table for your tires. I have 315/70/17 on my Dodge diesel and run 35 front 32 rear,no bouncing, very nice ride for a 3/4 ton truck!

2X!

Every tire manufacturer has a load chart for their tires. It's based on how much weight is on the tire, and how much air is needed to support that weight. That's a good start and doing a chalk test on your tires.

[TankerZak]

Was the oscillation a type of bouncing, or a side to side? And was it the front or the rear of the truck? Aka did the truck try and squat and waggle on you around corners?

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[1pieceatatime]

So about 1/8” play in frame-side track bar bushing when turning lock-to-lock. This I assume is a strong potential to be causing my problem, or is it normal/acceptable?

12second video:
https://youtu.be/cI9Si90KGUc

[1pieceatatime]

Was the oscillation a type of bouncing, or a side to side? And was it the front or the rear of the truck? Aka did the truck try and squat and waggle on you around corners?

Sent from my SM-G955U using Tapatalk

Side-to-side, front I think but with my weight up high in back any cornering has some component of rear roll to it.

[DamageWagon]

18k miles is fairly quick to lose a trackbar but very possible. I’d for sure recommend swapping your REAR trackbar for the Thuren unit, I think the booty wiggle these trucks have, especially with weight up high, is a big contributor. I’m a dealer for Thuren but for the front trackbar Is recommend checking out the Carli unit, there seems to be some issues going through right now with the bushings on the Thuren bar, not sure if it’s an isolated issue.

[DamageWagon]

I just saw your video, hard to tell but that doesn’t look too bad. It’s harder to diagnose the 14+ trackbar because there is such a thin amount of rubber between the housing and sleeve. They are not very apparent when they go bad, where the 03-13’s were very obvious when they were toast.

I’d do the rear trackbar, see how that feels. Also check out how it feels with the tent and tire removed.

[RustyPW]

The Carli front trackbar doesn't use ploy bushing at the frame mount. They use a bearing now. No flex. This is the bar I'm using now.

Here's my video. Yeah,it's bad. Your's is weak, going on bad.

phpBB [video]

Clickable link for Tapatalk

[DamageWagon]

The Carli front trackbar doesn't use ploy bushing at the frame mount. They use a bearing now. No flex. This is the bar I'm using now.

Here's my video. Yeah,it's bad. Your's is weak, going on bad.

phpBB [video]

Clickable link for Tapatalk

The current Carli bar does use a bushing. It is a uniball in the center, surrounded by a bushing, inside the housing.

[RustyPW]

Couple of pic's.

In the pic's. The top bar is the 2nd gen Carli bar. The bottom bar is the 1st gen Carli bar.

[DamageWagon]

The current Carli bar has their new ‘CUB’ Captured Uniball Bearing. It’s captured in a poly housing.

I still have the bar in your first pic Carli didn’t take kindly to me telling them I measured the housing at .035” out of round haha

[TankerZak]

I think it's most likely a combination of things but I think your feeling the rear track bar. And your weight and CoG is amplifying it. That thing should be changed at the factory before it ever left.

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[2wagons1driveway]

Crazy that the thuren bar frame bushing went so fast. I’ve had mine for five years plus and no issues with can still barely get grease in it because it’s so tight still. Changed my axle side joint to an emf after the first one went (two years old) and it’s been good ever since- I can also tighten the emf joint if it does get extra play, with the emf special tools- well worth the extra pesos to grab one of those instead of a regular xf heim


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[OffroadTreks]

Crazy that the thuren bar frame bushing went so fast. I’ve had mine for five years plus and no issues with can still barely get grease in it because it’s so tight still. Changed my axle side joint to an emf after the first one went (two years old) and it’s been good ever since- I can also tighten the emf joint if it does get extra play, with the emf special tools- well worth the extra pesos to grab one of those instead of a regular xf heim

I tend to believe Neil's assessment about the articulink vs the older trucks with the control arms.