I got 30000 miles out of the original front on my old '06 Road Glide.
Now of course riding habits,road surface will have a big impact from bike to bike.
I think 3/32" is still rideable unless there are other wear/balance issues.

 

Where are you in Pgh? Which dealer are you going to? If you want PM me, i'm also in Pgh and know a few good independent shops and a good dealership.

 

Did you double-check the depth yourself with your own tread depth tool? Maybe they lied to you about that to get you to buy a tire.

 

I bought a tread depth indicator, took measurements at a few locations. All said roughly the same, a little over 3/32s. Been checking pressure also. No signs of cupping. I took my bike there for 2 yrs for annual inspections, both times they said I needed new brakes. Went somewhere else last year, pads are fine. Will see this year again. It seemed like every time went to the stealership for something they looked for something else. I had an appt for the oil change, etc. It sat there for 2 days. I called and bitched, they said they had emergency work come in, a bunch of bull.

 

It is the techs and SW's job to upsale.

 

From the HD book. You can go down to 1/32 of tread. That's when you'll begin to see the wear bars. Less than 1/32 you need to replace the tire. Otherwise you will hydroplane on wet roads.