3500 continuous, rhythmic bounce on concrete highway

[AH64ID]

I've driven those Colorado highways many time and have had some luck in upgrading my truck. 1st) I removed my un-leveling kit that made a huge difference in reducing bounce, don't add a leveling kit, it really increases the bounce 2) lowered my f/r tire pressure to 65 when unloaded. 3) have a camper shell adding weight to the rear, 4) added sulastic shackles to my rear leafs (huge difference), 5) replaced factory dampers with bilstien. 6) switched tires. Now the truck rides better unloaded than loaded. rides great on concrete freeways no problems in the houston area which are all concrete practically and Colorado. In fact it rides so much better, that I find myself driving at 80+ on concrete roads as they barely disturb the truck. Which is a 3500 megacab as well. The biggest changes were adding the sulastic shackles, ditching the leveling kit, and lowering air pressure in that order. The shocks made the least difference. I'd suspect reducing unsprung weight would help, more advanced shocks that are frequency selective damping instead of singe valved, getting rid of solid axles....

That's still quite a bit of air pressure for unloaded, as you can run 6,170lbs on each axle (OEM sizes) at 65 psi.

 

[thecastle]

I don't disagree, I'm just saying that 65 was enough reduction for me to ride fine in conjunction with the other mods I've done. Lower won't make it worse!

 

[MarioM]

Is this kinda thing going to get better when towing decent weight? How is this not going to destroy a travel trailer?

Twoing weight does not fixes the issue, it is the same . I tow 10 to 20 thousand lbs regularly the bouncing and jumping does not goes away.

 

[Lord muta]

So I’ve had this problem in my Chevy 1500s and in my power wagon.

Some has to do with suspension stiffness and tire inflation etc. but what it comes down to is wheel base. I’m in Arizona (Phoenix) we have the 303 freeway. It’s got a huge portion that is concrete. I had 2 different chevys. One with the cab and a half so not 4 full doors.. it had no issues at all. My next Chevy had the 4 full doors just a few inches longer than my other Chevy. Better suspension and tires but I had the harmonic bouncing going on. Speed helps change where in the suspension rebound the sections of the road hit the truck. Faster was better. 80 rides nearly smooth 85 rides like my rebel did. Smooth as butter. Slow down and my power wagon bounces along like popcorn.

Don’t let it get you down. It’s just the way it is with a longer wheelbase or an HD truck