Glad I came across this post. I'll be sure to avoid Boulder Nissan. Tynan's might be hearing from me in a few weeks if I still have this knocking-like rattling noise on my new 07 OR Xterra after the break-in period is over (Only happens under constant heavier acceleration - up a pass on I70, for example).

I bought the X from Valley Nissan in Longmont, and they were great, but for servicing, I'll pick Tynan's for their participation in the offroading community.