33×12.50R15 and 285/70R17 are about the same height: 32.7″ and 32.9″ on average as listed by their makers (33.00″ and 32.71″ on paper).
Going from 33×12.50R15 to 285/70R17.
Lift is half the height difference, since the axle sits at the middle of the tire. The speedometer figure assumes it was set for 33×12.50R15 and uses the revolutions per mile the makers publish: at an indicated 60 mph you'd be doing 60.2 mph.
| 33×12.50R15 | 285/70R17 | Difference | |
|---|---|---|---|
| Listed height ″ | 32.50–33.02 | 32.70–33.15 | +0.14 |
| Size code height ″ | 33.00 | 32.71 | −0.29 |
| Height under load ″ | 31.7 | 31.8 | +0.1 |
| Width ″ | 12.50 | 11.22 | −1.28 |
| Listed width ″ | 12.1–12.8 | 11.4–11.6 | −0.9 |
| Sidewall ″ | 9.00 | 7.85 | −1.15 |
| Wheel ″ | 15 | 17 | +2 |
| Weight lb | 55.0–73.1 | 46.0–65.7 | −3.9 |
| Tread depth /32″ | 15–21 | 13–19 | −2.5 |
| Tires listed | 6 | 36 |
The same model in each size, by the heights the maker lists. Averages where a model comes in several load ranges.
| Tire | 33×12.50R15 ″ | 285/70R17 ″ | Taller by | Heavier by |
|---|---|---|---|---|
| BFGoodrich All-Terrain T/A KO3 | 32.50 | 32.80 | +0.30″ | −0.0 lb |
| BFGoodrich Mud-Terrain T/A KM3 | 32.50 | 32.80 | +0.30″ | +6.6 lb |
| Mickey Thompson Baja Boss M/T | 32.70 | 33.00 | +0.30″ | +3.0 lb |
| Mickey Thompson Baja Legend EXP | 32.90 | 33.10 | +0.20″ | +2.0 lb |
| Mickey Thompson Baja Legend MTZ | 32.70 | 33.00 | +0.30″ | +2.0 lb |
| Toyo Open Country M/T | 33.02 | 32.99 | −0.03″ | −9.0 lb |
0.14″ on average, going by the heights tire makers list: 33×12.50R15 tires are listed at 32.50–33.02″ and 285/70R17 at 32.70–33.15″. The size codes work out to 33.00″ and 32.71″, a 0.29″ difference the other way.
Almost none: the tire's radius changes by 0.07″. 285/70R17 is also 1.28″ narrower on paper, 0.64″ per side on the same wheel. Whether it fits depends on your vehicle, lift and wheel offset.
Barely: about 0.4% slow.
No. 33×12.50R15 fits a 15-inch wheel and 285/70R17 a 17-inch wheel.