Check and/or replace the rubber flex lines between the frame and the suspension parts- - - - -two up front and one in the rear. They deteriorate and collapse from the inside, and restrict fluid flow. "New" doesn't necessarily mean "good" since a lot of replacement parts for stovebolts are made offshore with poor or nonexistent quality control.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!