I noticed unusual wear pattern on the right front tire on my 2015 Newmar Baystar with 30,000 miles. Tire shows slight cupping pattern. I took the coach to a Freight-liner service center and they told me the king pins were worn. Because of that they couldn't do an alignment until the problem was fixed. The service manager quoted me $3,605.00 to fix the problem. I was astounded. I did a little research online and found that the Moog 8639B Steering King Pin Set would cost me $133.66. My questions are two fold. First, is king pen wear usual at only 30,000? Second, does anyone have experience on cost for this service? Thanks for any replies.