My G670s are four years old and have 35,000 miles. My old Toyos cupped on the edges like most seemed to do. My G670 on the drivers' side is OK and the passengers' side is wearing on the outside. I measured the tread depth the other day and the drivers' side is 11 to 12/32 and the passengers' side is 12 to 9/32, with the low number on the outside. The tires are not cupped like the Toyos did. I had the front end aligned 17,0000 miles ago, when I had noticed the wear on the passenger side. I run Koni shocks.
Now, my neighbors' Beaver has a passenger side tire that looks pretty much like mine, altho less mileage (don't know, but would guess he has under 15,000 on his three year old coach). His driver side looks OK.
Now I am wondering if this is due to the crown in the road and weight shift to the passenger side? Guess to really understand, I should get front end measurements.
Now, I had gone all around and measured my tread depth. The rears are basically at 11 to 10/32 and pretty evenly worn. The original depth according to the Goodyear site is 16/32, which seems to imply about half the tread life if you were to replace at 1/8 to 1/16 inch.
2001 34' Alpine Coach
2008 Jeep Rubicon or 2012 Ford F150 4x4 Lariat towds
or a couple of different trailers
Retired in Apple Valley, California