As much as we would love to sell you more parts we should point out that for 90%+ of our customers aftermarket trailing arms are not necessary. They add advanced suspension adjustment that the average person doesn’t need, but they do have the added advantage of reducing unwanted movement in the rear suspension. Trailing arms primarily address fore aft movement. They will noticeably tighten things up under hard acceleration and braking. We wouldn’t put these at the top of the priority list, but if you are trying to win a time attack, and you have addressed everything else they can be a worthwhile upgrade.