W900 shakes sways side to side

Hi all new here….I’ve got a quad axle 2007 w900 530 isx 18spd Hendrickson primaax suspension dump truck it was a conversion double framed past the front hangers and front raised a bit….ever since I bought this truck it’s always had this kind of sway from side to side or lean from side to side even when driving on flat ground(feels like your driving on gravel road lol) gets even worse in job sites….funny thing is if I park it over the weekend Monday morning it will ride like a dream and shift like butter for half a day…then the rest of the week it rides like crap….and I have trouble shifting (a little grind and kinda like a bump in each gear) I’ve been at this for about 3 years and I just can’t make it go away I’ve replaced the rear motor mounts,cab mounts,whole front end kingpins,tie rods,leaf springs and bushings shocks balanced the tires,rear shocks and all torque rods, complete alignment and bushings,changed the air leveling valve,air bags, clutch basically everything lol and I’m still stumped…my air pressure does stay around 110 most of the time stopped or driving ….anybody have any other ideas?

 

Not that I know of

 

Never really had a problem off road with it….but yea I changed out the leveling valve and played with different heights still same situation….i feel like it starts in the front and works its way to the back….idk if it has anything to do with the air system and or motor/transmission because it’s so weird that when it rides good it shifts good and it only rides good on Monday mornings lol

 

I have 2 times from 2 different shops

 

now that you mention the way the airbags are plumbed it does lean to the passenger side just a tab bit never really looked into that till now lol….


QUOTE="Rideandrepair, post: 13240627, member: 168603"]Sounds like it gets higher and rides rough. As if it’s not dumping air.Leveler good, height right. Hmmm. What about the way air bags are plumbed. The old WS sometimes had separate leveling valves for each axle. Others use to plumb the air bags on the later single valve systems together. Running air lines to all air bags, instead of just jumping from bag to bag in a row, like factory had them. The idea was to keep all the bags equal. My WS rode rough loaded unless I raised the air ride, empty I had to lower it. It was a Hendrickson suspension. I considered some type of manual cab mounted shut off valve, or an adjustable cable operated lever arm. Finally traded it for a Classic. Lol. Too bad, it was a beautiful Truck. I loved it. But it beat me up. After back surgery, I ran it a year. Decided it had to go, or quit driving.[/QUOTE]