Long enough to get old, hard, slippery and full of cracks. If you run 25-30k+ per year, that would be a way to go.
If not, you will never make your investment back. Do the math on the wheel & tire costs up front vs. replacing your existing tires once a few years from now. What are we talking, 2 to 1 max life difference, without considering age and non-tread wear issues?
Scroll down to the bottom of the page and you'll see them listed for our trucks. They're pricey though, if you were to buy new and with tires it's going to cost about $2500.00 - 3000.00 with shipping. I looked into them for the added load capacity since I have a truck camper, but the cost detered me. Many people that haul heavy loads use them because of tread life and longevity. I also stayed away due to the 19.5" rims and all xx.5" have a different type of bead that can't be aired down for 4-wheeling or beach use.
I like the look of a larger diameter wheel. But the look of a polished wheel or with a SS wheel simulator. I looked up that wheel chart and there is only one steel wheel available for one chevy application and it's $170 each. I doubt that I'm going to be able to find a SS wheel simulator that's 8-lug x 6.5".
Maybe go round 2 with redrilled wheel pattern or find the newer 99' and up ford axles for my rig. I'm building an old 61' chevy short bus with F350 4x4 running gear. Have stock wheels and tires now, but looking to upgrade to what I like in the future, instead of buying new 16" tires.