volvo vibrations

50 psi on around 43.500lbs load ,and bobtail has around 5-6 psi so you right alla5oh ,mechanic also there is not enough preasure on rear end bags, tomorow when gstart the trip i try do what you said dumping air and i will post results.......now about height, few mechanics which tried to find a problem in my truck says air ride valve has nothing to preasure , air ride valve ONLY operates changing height with preasure from supply air line ( it doesnt drop or rise preasure going to air bags),,,,,,,,mechanics change height in my truck few times and no matter it was set on very low or middle or heigh hole (5 holes in beam under air bags) no change in driving, they explaining me that low preasure on empty or light load doesnt squeze air bags enough to rise preasure to stop vibrations, on the other hand ,heavy load preasure air bags much more then light load or weight of empty trailer and air preasure in air bags is rising pretty much enough to stop vibrations,,,,,,what you thiink but physicly sounds good to me

 

thanx you all for reply, ok so there is nothing to adjust preasure coming to air ride valve ?????? it just the load the heavier load more preasure,light load less preasure ,smart and simple,,,,but my mechanic is pointing that there is a working air preasure supplying lets say from 15-70 psi ??? or you guys think no matter what preasure air ride operates it has to be right and correct, mr. heavyd thanx for hendrix linkage is very useful, and explaination about rear end,,,,now know how everything work i got mess in my head what in my truck is good and what is wrong.......mechanic is pointing to some eletric/air valve which is under the sleeper floor ,on frame crossmember (there are 4 of them ) i dont know what they are,,,,he says on of them is to drop or inflate air bags from the cab using switch, he says we check and change all other parts even air lines to exlude broken piece of the air system, but he has no idea how to check or how this electric/air valve operates all he says is maybe this thing has some inner leak or something got stuck inside cousing vibrations through other parts in air system ??????? more questions then answers .....

 

full system preasure??????????? so my air ride valve operates on less then half of it........about ride height,i found procedure on this forum and ask volvo dealer spec, both method are slightly different but make the same height ,i checked that myself, height for my tall frame and 24,5 inch wheels must be between 7,5 and 8 inch, so my height is correct 7,5 ,,,,,,all driveshafts and center bearing are brand new and been checked 100 times for any possible loose or other damages nothing found,,,,,how about those alectric/air valves, do you have any knowlegde about them????

 

yeeep, found front engine mount cracked and replaced, rest are fine.....