Toyota Tacoma 2nd gen: the width decision, not the height

Two ways to reach 33 inches

285/75R16 measures 32.83 in and is 11.22 in wide. 33x12.50R16 measures 33.00 in and is 12.50 in wide. Between them: 0.17 in of height and 1.28 in of section width.

From 265/70R16 at 30.61 in, the metric size is +2.22 in and 7.27%; the flotation size is +2.39 in and 7.82%. The height difference is trivial and the width difference is not — 2.07 in of extra casing width against 0.79 in, measured at the point that meets the inner fender first.

Anyone deciding between them on the strength of the "33" in one name and the "285" in the other is comparing the wrong dimension.

The three factory starting points

245/75R16 at 30.47 in, 265/70R16 at 30.61 in and 265/65R17 at 30.56 in. The whole range occupies 0.14 in, so the trim you have shifts the arithmetic by less than half a percent and every figure on this page applies to all three.

The 17-inch fitment is the odd one in packaging terms rather than in height: same 265 mm width as the 16-inch tire, half an inch less sidewall, identical rolling diameter to within 0.04 in.

What the step actually costs

Take the most common route on this platform, 265/70R16 to 285/75R16:

• Diameter: +2.22 in, 7.27%
• Section width: +0.79 in
• Ride height at the axle: +1.11 in, which is half the diameter change
• Speedometer: an indicated 70 mph is 75.1
• Odometer: 100 indicated miles is 107.3 covered

The ride-height figure is the one people misread. A tire 2.22 in taller lifts the axle by half that — the other half goes upward from the axle centre toward the fender, where the clearance question lives.

Age is now part of the calculation

This generation ran from 2005 to 2015, so every example is well into its life, and two effects compound on an older truck.

Tread depth is part of the rolling radius: a tire replaced at 4/32 in from a 16/32 in start has lost 0.75 in of overall diameter, which is a third of the entire upgrade step above. A worn set of 285/75R16 measures closer to the factory diameter than a new set does.

And suspension that has settled over two decades changes the clearance answer in the other direction, without changing any tire dimension at all.

Axle ratios are not recorded here

Nothing above needs one. It is worth saying what the blank does and does not imply on a truck this old: it is not a claim that the figure is unknowable, only that it was not confirmed — and on a fifteen-to-twenty-year-old midsize pickup, the ratio on the tag is in any case better evidence than any model-level figure would be.

The relationship that always holds: a 7.27% diameter increase behaves exactly like a 7.27% numerically lower final drive, whatever ratio is fitted. With your truck's actual figure — from the differential tag — the gear ratio calculator returns both the ratio that puts engine speed back where it started and the closest ring-and-pinion actually catalogued.

The variable the choice above leaves out

Every figure on this page is computed from a size code, and a size code carries only one of the wheel's two dimensions. 33x12.50R16 names a 16-inch diameter and says nothing about width; the factory wheel's width is stamped on the wheel and recorded nowhere here.

It is worth raising because the width term is the one that moves. A flotation casing fitted narrower than the reference rim its 12.50 in was quoted on measures narrower and stands very slightly taller than published, at a rate of about a fifth of an inch for every half inch of wheel. So the width gap between the two candidates above is not a fixed quantity — it closes or opens depending on what they are mounted on, and the only way to know which is to read the wheel and the tire's own data sheet. Rim width to tire width has the approximation, and it is the correction most fitment discussions leave out.

Where the page stops and the tape measure starts

Nothing here says a tire clears. On this platform the front upper control arm and the inner fender are the usual limits, and both respond to section width and wheel offset rather than to diameter. That is the opposite of the way the conversation usually runs, where the number people quote is the call size in inches — a figure that says nothing at all about the dimension doing the touching.