Lets use 33" Duratracs as an example, and lets use Discount Tire Direct for our pricing:
15" package (that's what she said.
33x12.5x15 Duratracs = $197ea
15" MB72s = $99ea
Non-TPMS valves = $3ea
Total for 5 mounted, balanced, and shipped = $1,495
285/70/17 Duratracs = $278.77ea
Total for 5 shipped, but not mounted or balanced of course = $1,393.85
So, then you have to take the newly acquired 17" tires to a shop and have them mounted and balanced. At my local Discount Tire, you are looking at an environmental fee of $5.14, tire disposal fee of $1.75, and installation and lifetime spin balancing fee of $16 for each of the 285/70/17 tires. So that is $114.45 (+ tax if applicable). So, you are looking at $1508.30
if you go with the 17" package.
But, what if you experience rubbing issues with the 285s on your stock wheels (6.25" backspacing) and decide that you need wheel spacers. Tack on another $200 for 1.5" Spidertrax spacers. Now you are at $1,708.30
. $210+ more than the 15" wheel AND
None of the setups above are taking into account any forum discounts, or mail in rebates or any of that stuff. But, you can subtract $125 from each of the totals really, since forum members get $50 off of 5 tires at DTD and you can get the $100 mail in rebate for select Goodyear tires (Duratracs are included) for joining treadlightly.org for $25.
For what it's worth, I recently purchased 5 16x8.5 Level 8 Strike 5s mounted on 285/75/16 Falken Rocky Mountains with full replacement certificates for $1,580 mounted, balanced, and shipped to my door.