I have a 2002 grand cherokee and the driver's side lower spring seat is rusted away causing the spring to sink lower and make the jeep sit lower on one side. Is there any way to replace the rusted out part that is mounted to the axle?

 

Remove the axle and take it to a good 4x4 shop and they should be able to make it right.

 

drive it to a 4wd repair shop and see if they can make a repair

if not, entire used front D30 assemblies can be quite cheap, as they usually long lasting