[gmc684x4]

Big block or small block make a big difference in front springs 1/2 ton to 3/4 ton less so as it is the back spring do all the carrying capacity

That you can not pump grease into the a arm bushings i find a concern and would disassemble to find out why could cause binding issues

Ask your friend if they where for a big block front springs

Does the front end ride higher then the back ?