Coil Springs As many of you with lifted Jeeps know, not all aftermarket coil springs are made equal. Some sag more than others, and even different corners on the same Jeep can sag differently. So, the first step in buying used coils is to ask friends who have springs from the same company how much they sag. Then, when you get there, lay the coils from like ends of the Jeep side-by-side and check for a difference in unsprung height. Any unsprung difference will translate into much more sprung height difference, and unless you want to use coil spacers to level out your Jeep, you might want to pass. Also, visually inspect them for wear. Tires rubbing paint or powder off isn’t a big deal, but gouges in the steel from sway bar end links, bumpstop buckets, or steering linkage could lead to failure down the road.