I lowered my 2012 1.5" with some new SR springs. I wanted to break them in easy so for the first week or so, I drove slow, like 20mph around post(Army), and finally decided to take a long trip. I drove about 100 miles and I started hearing a faint rattling in the rear of my pony. Only between 50-60 mph, though. Could that be them settling in or maybe something loose? Anyone got any ideas?