Better ride when not towing?

[Gator398]

Is it possible, to make a dually truck not shake like an earthquake on expansion joint roads when the trailer is off???!!

I have read about the kelderman 4 link or whatever, is that our only option?

[Grit_dog]

Concrete roads? Nope, but it should be worse with the trailer on.
Just Rough riding? Lower tire pressure.

[Beverley_Ken]

I'm not a truck person, but read your owners manual and/or door sticker for tire pressure, empty and loaded. If they are overinflated for the load they are carrying, you will get the ride you are describing. Best would be to get the truck weighed fully loaded with trailer, front and rear axle plus trailer axles. Then have the truck alone,as your daily driver weighed, again axle weights.
Then use the tire manufacturers chart for your particular tire to see the recommended pressure for each tire/axle. You might get a smoother ride for next o $0.00

Ken

[BenK]

All things will vibrate from some sort of input. When the input harmonic matches the thing’s natural harmonic and if the input continues to input, the thing will vibrate more within the same frequency.

Your running over the expansion joints sets up an input to your truck. Your speed dictates the frequency of the input to your TV.

Slowing down and/or speeding up will change the input frequency to your truck.

As for you trucks harmonic...the things that are part or contribute to its harmonic are the tires, suspension (shocks, bushing, shocks, architecture, etc), the body bushings to frame and a big ETC.

The Kelderman suspension you mention changes the suspension architecture and the air bags adjust what the input’s amplitude & suspension response...AKA tunes the suspension harmonic

Other than changing your speed, changing the tire PSI changes its harmonics, change the shocks and can go either way...more or less dampening, and everything else in that food chain.

Easiest and lowest cost is changing your speed...

[MT_BOB]

Are you 12?