There is a good article in Wing World this month by Stu Ottman on the rear spring preload. He gives a quick procedure to determine when the spring is actually starting to be compressed. A reading of 3 or below on the scale is good, but he says if it is 5 or below it should be good to go. I checked mine and it is way out of tolerance. '01, 38K. I am betting that there are more on the road OOT, than within tolerance, especially if they are 3-4 years old.