I have a '77 3/4 ton suburban. I want to lift it 4 inches, but I also want to retain most of its towing capacity. I tow fairly heavy trailers farily frequently when helping out my father's construction business. Stuff his Durango can't handle like flatbeds with bobcats loaded on them and such. What are my options? I know that blocks suck and the shackle flip is not for towing. I'm worried about new springs being too lightweight. Are there 3/4 ton lift springs that would maintain my towing/load capacity?