33×12.50R17 and 285/70R17 are about the same height: 32.8″ and 32.9″ on average as listed by their makers (33.00″ and 32.71″ on paper).
Going from 33×12.50R17 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 33×12.50R17 and uses the revolutions per mile the makers publish: at an indicated 60 mph you'd be doing 60.2 mph.
| 33×12.50R17 | 285/70R17 | Difference | |
|---|---|---|---|
| Listed height ″ | 32.50–33.00 | 32.70–33.15 | +0.09 |
| Size code height ″ | 33.00 | 32.71 | −0.29 |
| Height under load ″ | 31.8 | 31.8 | +0.1 |
| Width ″ | 12.50 | 11.22 | −1.28 |
| Listed width ″ | 12.0–12.5 | 11.4–11.6 | −0.9 |
| Sidewall ″ | 8.00 | 7.85 | −0.15 |
| Wheel ″ | 17 | 17 | same |
| Weight lb | 59.9–70.9 | 46.0–65.7 | −9.7 |
| Tread depth /32″ | 15–21 | 13–19 | −2.5 |
| Tires listed | 10 | 36 |
The same model in each size, by the heights the maker lists. Averages where a model comes in several load ranges.
| Tire | 33×12.50R17 ″ | 285/70R17 ″ | Taller by | Heavier by |
|---|---|---|---|---|
| BFGoodrich All-Terrain T/A KO3 | 32.50 | 32.80 | +0.30″ | −4.0 lb |
| BFGoodrich Mud-Terrain T/A KM3 | 32.50 | 32.80 | +0.30″ | −0.7 lb |
| General Grabber X3 | 33.00 | 32.70 | −0.30″ | −5.0 lb |
| Mickey Thompson Baja Boss A/T | 32.80 | 32.90 | +0.10″ | −12.5 lb |
| Mickey Thompson Baja Boss M/T | 33.00 | 33.00 | +0.00″ | −4.0 lb |
| Toyo Open Country A/T III | 32.52 | 32.81 | +0.29″ | −8.2 lb |
| Toyo Open Country M/T | 32.76 | 32.99 | +0.24″ | −6.3 lb |
| Toyo Open Country R/T | 32.76 | 32.99 | +0.24″ | −7.0 lb |
| Toyo Open Country R/T Pro | 32.80 | 32.76 | −0.04″ | −11.1 lb |
0.09″ on average, going by the heights tire makers list: 33×12.50R17 tires are listed at 32.50–33.00″ 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 0.05″. 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 0.3% slow.
Both fit a 17-inch wheel. Wheel widths approved for both run from 8.5″ to 10.0″.