Duster has spool and 4.88 gears. Has leaf springs. Previously body would lift about 5 1/2 inches. Last run drivers side lifted as normal but passenger side just sits and leans all the way down track. Stationary car sits level and only leans under power. Pulled the axles and no problems. Shock is workiing fine. Don't see a broken spring.

Check the spring perch it could be ripping free or
the right spring is shot in the front allowing it
to flex alot... the front holds the axle in place and
gives it the lift... the rear of the spring is what
holds it up... if it started sorta quick I would look
at the perch first... also is this a dana rear end..
the tube can be rotating in the housing

Not a Dana. 8 3/4

Mr. Peabody thank you. You are correct. The welds on the spring perch where they were relocated have broken. Thank you again for your response