Mine got real knobby...(again from loss of oil in shocks).Bought my Bushtec Quantum GL trailer 2 years ago.
Curious how many miles I should expect from the tires.
This all depends on how long the shocks last. I got 25k out of my tires on my bushtec. I probably could have gotten more miles out of them, but on one ride I thought I ran over some oil on the road, cleaned the wheel wells and tires up and kept using the trailer the next year...only to find out the tires wore out and the root cause was because the shocks lost their fluid/oil.
Also, not being familiar with the tread design, how do I tell when they are ready to be changed out?