Ratio to restore
The numerically higher axle ratio that returns the truck to its stock effective gearing on larger tires.
Gear ratio
Find the right gear ratio for bigger tires on a Tacoma or midsize pickup.
Enter your stock and new tire size with your current axle ratio to see the regear that restores stock drivability.
Summary: This calculator finds the axle ratio that restores stock gearing after a tire size change on a Tacoma or other midsize pickup, and the nearest ratio gear shops actually stock.
Updated
What gear ratio restores stock gearing on bigger Tacoma tires?
This chart shows the axle ratio that brings a Toyota Tacoma back to its stock effective gearing after a tire size change, for the 4th gen (2024-2026) and 3rd gen (2016-2023) factory ratios. Each cell is the exact restoring ratio (factory ratio × new diameter ÷ stock diameter) and the nearest ring-and-pinion ratio shops stock, from the same math as the calculator below. It is the ratio that restores stock gearing, not a recommendation: many owners run 33s on factory gears, and some choose a ratio above the restoring figure for extra low-end.
| Tire size | Class | Diameter | 4th gen auto (3.58) | 4th gen manual (4.30) | 3rd gen auto (3.91) | 3rd gen manual (4.30) |
|---|---|---|---|---|---|---|
| 265/70R16 | 3rd gen stock | 30.6 in / 777 mm | Smaller than stock | Smaller than stock | 3.91:1 (factory) | 4.30:1 (factory) |
| 265/70R17 | 4th gen stock | 31.6 in / 803 mm | 3.58:1 (factory) | 4.30:1 (factory) | 4.04:1 (nearest stocked 4.10:1) | 4.44:1 (nearest stocked 4.56:1) |
| 255/75R17 | ~32 in | 32.1 in / 814 mm | 3.63:1 (nearest stocked 3.91:1) | 4.36:1 (nearest stocked 4.30:1) | 4.09:1 (nearest stocked 4.10:1) | 4.50:1 (nearest stocked 4.56:1) |
| 285/70R17 | 33 in (the common 33) | 32.7 in / 831 mm | 3.71:1 (nearest stocked 3.91:1) | 4.45:1 (nearest stocked 4.56:1) | 4.18:1 (nearest stocked 4.10:1) | 4.60:1 (nearest stocked 4.56:1) |
| 285/75R17 | 34 in | 33.8 in / 859 mm | 3.84:1 (nearest stocked 3.91:1) | 4.60:1 (nearest stocked 4.56:1) | 4.32:1 (nearest stocked 4.30:1) | 4.75:1 (nearest stocked 4.88:1) |
| 315/70R17 | 35 in (metric) | 34.4 in / 873 mm | 3.90:1 (nearest stocked 3.91:1) | 4.67:1 (nearest stocked 4.56:1) | 4.39:1 (nearest stocked 4.30:1) | 4.83:1 (nearest stocked 4.88:1) |
| 35x12.5R17 | 35 in | 35.0 in / 889 mm | 3.97:1 (nearest stocked 3.91:1) | 4.76:1 (nearest stocked 4.88:1) | 4.47:1 (nearest stocked 4.56:1) | 4.92:1 (nearest stocked 4.88:1) |
| 37x12.5R17 | 37 in | 37.0 in / 940 mm | 4.19:1 (nearest stocked 4.10:1) | 5.03:1 (nearest stocked 4.88:1) | 4.73:1 (nearest stocked 4.88:1) | 5.20:1 (nearest stocked 5.29:1) |
How do I read this table?
- 4th gen columns start from a 265/70R17 factory tire (31.6 in / 803 mm); 3rd gen columns start from 265/70R16 (30.6 in / 777 mm). Other factory sizes such as 245/70R17 or 265/70R18 shift every figure, so enter your own stock size in the calculator.
- Exact ratio: what keeps engine RPM at a given speed and gear the same as stock on the new tire. Nearest stocked can land above or below it; going above trades a little highway RPM for low-end, going below leaves the truck slightly taller-geared than stock.
- Nearest stocked snaps to the ring-and-pinion ratios the calculator uses: 3.91, 4.10, 4.30, 4.56, 4.88, 5.29. Which of these a gear maker offers for your specific axle varies, so confirm with a gear shop.
- Each column restores that truck's own stock gearing. The generations pair their axles with different transmissions, so compare a cell with its own column's factory ratio, not with another column.
- Regear the front and rear axles together to the same ratio; e-locker trims need a locker-compatible gear kit.
Run your exact stock size, new size, and axle ratio in the Gear Ratio Calculator below. Related: Cruising RPM calculator · Do you need to regear? · 33 vs 35 inch tires.
How does this Tacoma gear ratio calculator work?
A taller tire acts like a numerically lower axle ratio: the truck covers more ground per engine revolution, so it feels slower off the line and the transmission hunts for gears on grades. The calculator works out how much gearing a Tacoma or other midsize pickup truck loses on a bigger tire, the exact axle ratio that would win it back, and the nearest ring-and-pinion ratio a gear shop can actually install.
What do I enter?
- Your stock tire size, the one the truck's computer and gearing were set up for.
- The new tire size, metric or flotation.
- Your current axle ratio, picked from the factory Tacoma presets (3.58, 3.73, 3.91, 4.10, 4.30).
What does it show?
- Ratio to restore: the axle ratio that brings engine RPM and shift feel back to stock on the new tire.
- Nearest stocked: the closest ratio from the common regear list.
- Effective ratio now: what your current gears behave like on the taller tire, before any regear.
- Community regear guidance for that tire diameter and the 0.12 × diameter daily-driver rule of thumb, shown as context rather than as the answer.
What gear ratio does 265/70R17 to 285/70R17 need on a 3.58 axle?
Take a 2026 TRD Off-Road with the 2.4T eight-speed automatic (the 3.58:1 axle preset) moving from its factory 265/70R17 tires to 285/70R17. The tire grows from 31.61 in to 32.71 in, so the truck now behaves like a 3.46:1 axle, 3.4% less gearing. Restoring stock feel takes 3.58 × 32.71 ÷ 31.61 = 3.71:1, and the nearest stocked ratio is 3.91:1.
For contrast, the community guidance the calculator shows for a 32.7 in tire is 4.88 (4.56 for mostly-street 33s), and the rule of thumb lands near 3.93:1. Both sit above the restoring ratio because they aim for extra low-end on a loaded or off-road truck, not just a return to stock. The table runs the same size change on every factory axle the calculator offers.
| Factory axle preset | Effective ratio on 285/70R17 | Ratio to restore | Nearest stocked |
|---|---|---|---|
| 3.58: 4th gen 2.4T 8-speed auto | 3.46:1 | 3.71:1 | 3.91:1 |
| 3.73: 2nd gen 4.0L V6 (common) | 3.60:1 | 3.86:1 | 3.91:1 |
| 3.91: 3rd gen 3.5L V6 6-speed auto | 3.78:1 | 4.05:1 | 4.10:1 |
| 4.10: 2nd gen 4.0L V6 (some) | 3.96:1 | 4.24:1 | 4.30:1 |
| 4.30: 3rd / 4th gen 6-speed manual | 4.16:1 | 4.45:1 | 4.56:1 |
How is it different from a generic calculator?
- Tacoma axles as presets: every factory ratio from the 2nd gen 4.0L V6 through the 4th gen 2.4T is a one-tap choice, so the starting point is your truck's real gearing rather than a typed guess.
- The restoring ratio is kept separate from advice: the exact ratio, the nearest one shops cut, and the community rule of thumb are shown side by side, so you can see when a recommendation overshoots stock on purpose.
- Visible math: restore = current ratio × new diameter ÷ stock diameter; effective = current ratio × stock diameter ÷ new diameter. Diameters come from the size code, and each example size links to its Tacoma size page for what it takes to clear.
Do I need to regear a midsize pickup for 33 inch tires?
Not always. On the 4th gen automatic Tacoma's 3.58 axle, a 285/70R17 softens gearing by about 3.4%, which many owners live with on a lightly loaded truck. A regear starts to pay off when the truck is heavy with armor, a roof tent, or a trailer, or when the transmission keeps downshifting on highway grades. Any midsize truck works the same way: compare your effective ratio with the restoring ratio before you decide.
Related: 265/70R17 on a Tacoma · 285/70R17 on a Tacoma · RPM calculator.
What it does
What does this tool do?
Effective ratio lost
The lower effective ratio you actually run if you keep the stock axle with bigger tires.
Tacoma regear guidance
Rules of thumb by tire size, factory ratios by generation, and the nearest ratio shops actually cut.
Which related tools and guides should I use next?
Where do these numbers come from?
The restoring ratio is your axle ratio times the new diameter over the old diameter, then snapped to the nearest ratio shops stock. Factory differential ratios come from Toyota's brochures, so you can confirm your own truck's starting ratio by year and transmission.
- Toyota 2023 Tacoma eBrochure: 3rd gen differential ratios (3.909 automatic, 4.30 manual)
- Toyota 2024 Tacoma eBrochure: 4th gen differential ratios (3.583 automatic, 4.3 manual)
- Tire geometry: computed from the numbers in each size code with this site's published formulas (no outside data)
Gear Ratio Calculator for Tire Size FAQ.
Most owners moving to 33s regear to 4.88, or 4.56 for a mostly-street truck. Enter your exact sizes and stock ratio above for the calculated target.
4.56 is the milder, more street-friendly choice for 33s; 4.88 restores more low-end torque and is the common pick for 33s that see trail use or added weight.
Yes. The front and rear must be regeared to the same ratio together, and e-locker trims need a locker-compatible gear kit.
On a 4th gen automatic Tacoma (3.58:1 axle) moving from 265/70R17 to 35x12.5R17, the truck behaves like a 3.24:1 axle, 9.7% less gearing. Restoring stock feel takes 3.97:1, and the nearest stocked ratio is 3.91:1. The same math applies to any midsize pickup: enter its stock size and axle ratio above.