Do you keep original tires on rv when going to Alaska?

is it worth looking at Costco?

Good question , Gary. I remember reading somewhere years ago, that Costco Tires were classed as 'Club Tires' and had a shorter tread life. They were the same grade that manufacturers put on their new vehicles. This applied to Michelin tires, but could have been applicable to other brands, as when I mentioned this to my Mazda dealer, they said they had noticed that original tires had always worn out faster than their replacements.
I have never been able to find that info since.