If your frame is indeed very good to go, I'd switch all 4 springs myself. The cost would be approximately $100 as well as transport and any hardware you should change. I say all four simply because you want them to match and if two has sagged it is https://holdenedaul.levitra-wiki.com/8007361/what_does_a_bent_frame_do_to_a_car_things_to_know_before_you_buy