Just came back from the Rally (in Syracuse) and it seems to be the consensus that you replace ties at 5-6 years. My tires were made on 9/07 so I am ready to bite the bullet. Got a quote from a local, ...
I just got a quote on Samson tires in 275/70R22.5 of $375/ea, out the door. That will probably be my next tire, as I have several RV friends that have gone to them and are very happy, plus several of the larger local trucking companies have made the switch to Samson and are very happy with the results.