I know before I ask this question there are many variables but I need some opinions on how many more miles I might expect before replacing my OE Stones. I have about 8500 miles on my 07' and the front tire is at 4/32 and the rear is at 5/32. I have a 2700 mile trip coming up and will be traveling 2 up pulling my trailer (about 130 lbs). Do you think I have plenty of tread left. Thanks......