Data sheet TS-285/65R20 · Size
285/65R20 in inches
285/65R20 is 34.6 in (879 mm) in overall diameter by the formula. It turns 583 revolutions per mile (362 per km) and has a 11.2 in (285 mm) section width nominally.
Fig. 1 — Cross-section
Table 1 — Nominal dimensions
| Item | in | mm |
|---|---|---|
| DOverall diameter | 34.59 | 879 |
| ASection width | 11.22 | 285 |
| BSidewall | 7.29 | 185.3 |
| CRim | 20 | 508.0 |
| Circumference | 108.7 | 2,760 |
| Revs per mile · km | 583 | 362 |
| Flotation size printed | 35X11.50R20LT | Mickey Thompson |
|---|---|---|
| Measuring rim | 8.5″ | Nitto LT |
| Approved rims | 8.5–10.0, 8.0–10.0″ | 9 LT tires |
Table 2 — Measured range
34.57–34.80″overall diameter, 9 tires from 5 makers (math: 34.59″)
53–69 lbweight, 9 LT versions
15.8–18.5/32″new tread depth
3,860 lbmax load per tire, 8 of 9 LT versions list it, as published
9 LT · 0 Pversions in the makers’ tables we read
All 9 tires ↓Table 3
9 tires in 285/65R20, as published
One row per model and type, from each maker’s size table. LT first, then P-metric; sorted by diameter.
The math says 34.59″. 9 tires from 5 makers measure 34.57″–34.80″. Tallest here: Nitto Ridge Grappler (hybrid terrain), 34.80″. Check the maker’s number before you buy for a tight fit.
| Tire | Type | Diameter | Width | Rims, in | Weight | Tread | Max load |
|---|---|---|---|---|---|---|---|
| Nitto Recon Grappler A/Tnittotire.com · Oct 15, 2026 | LT · E 127/124S | 34.57″ | 11.50″ | 8.5–10.0 | 60.3 lb | 16.0/32″ | 3,860 lb @ 80 psi |
| Nitto Terra Grappler G3nittotire.com · Oct 15, 2026 | LT · E 127/124S | 34.57″ | 11.50″ | 8.5–10.0 | 59.5 lb | 16.0/32″ | 3,860 lb @ 80 psi |
| Firestone Destination X/Tfirestonetire.com · Oct 15, 2026 | LT · E 127S | 34.60″ | — | 8.0–10.0 | 53.3 lb | 16.0/32″ | — |
| Kumho Road Venture AT52kumhotireusa.com · Oct 15, 2026 | LT · E 127/124S | 34.60″ | 11.50″ | 8.5–10.0 | 59.3 lb | 16.0/32″ | 3,860 lb @ 80 psi |
| Mickey Thompson Baja Boss A/Tmickeythompsontires.com · Oct 15, 2026 | LT · E 127Q | 34.60″ | 11.50″ | 8.0–10.0 | 69.0 lb | 18.5/32″ | 3,860 lb @ 80 psi |
| Toyo Open Country A/T IIItoyotires.com · Oct 15, 2026 | LT · E 127/124S | 34.60″ | 11.50″ | 8.5–10.0 | 56.0 lb | 16.5/32″ | 3,860 lb @ 80 psi |
| Toyo Open Country R/T Trailtoyotires.com · Oct 15, 2026 | LT · E 127/124R | 34.60″ | 11.50″ | 8.5–10.0 | 61.0 lb | 16.5/32″ | 3,860 lb @ 80 psi |
| Toyo Open Country H/T IItoyotires.com · Oct 15, 2026 | LT · E 127/124R | 34.60″ | 11.50″ | 8.0–10.0 | 60.0 lb | 15.8/32″ | 3,860 lb @ 80 psi |
| Nitto Ridge Grapplernittotire.com · Oct 15, 2026 | LT · E 127/124Q | 34.80″ | 11.50″ | 8.5–10.0 | 63.7 lb | 16.4/32″ | 3,860 lb @ 80 psi |
§ 1
Nominal dimensions
By the formula 285/65R20 has an overall diameter of 34.6 in (879 mm). The section width is 11.2 in (285 mm) and the sidewall height is 7.3 in (185 mm).
Circumference is 108.7 in (2,760 mm). That gives 583 revolutions per mile (362 per km). These are unloaded nominal numbers calculated with the standard tire math.
§ 2
Published measurements
Tire makers list nine 285/65R20 items from five brands, all as LT sizes and all showing load range E. Published overall diameters run from 34.57 in to 34.8 in, versus 34.59 in by the formula (range 0.0% to +0.6%).
Weights in maker tables run from 53.3 lbs to 69 lbs. New tread depths run from 15.8/32 in to 18.5/32 in. Makers also publish approved rim widths and the maximum load rating on the sidewall (49 CFR 571.139).
- Nitto Recon Grappler A/T — overall diameter 34.57 in; weight 60.3 lbs; tread depth 16/32 in. (Nitto)
- Toyo Open Country A/T III — overall diameter 34.6 in; weight 56 lbs; tread depth 16.5/32 in; Toyo lists 601 revs per mile. (Toyo)
- Mickey Thompson Baja Boss A/T — overall diameter 34.6 in; weight 69 lbs; tread depth 18.5/32 in; maker lists equivalent 35X11.50R20LT. (Mickey Thompson)
§ 3
Closest sizes
The ±3% overall-diameter window is a shop rule of thumb for neighbor tables, not a law or a vehicle maker specification. Sizes near 285/65R20 include 275/65R20, 295/65R20, 315/60R20 and several 35-inch nominal tires.
Changing diameter alters indicated speed, revs per mile and static axle height. For example, 315/60R20 is about +0.9% (diameter +0.30 in / +8 mm); at an indicated 60 mph the true speed is 60.5 mph and revolutions go 583 → 578. A 35x11.50R20 is about +1.2% (diameter +0.41 in / +11 mm); at an indicated 60 mph the true speed is 60.7 mph and revolutions go 583 → 576.
- See a side-by-side comparison at the comparison tool.
- For a focused match against 275/65R20 see 275/65R20 vs 285/65R20.
Fig. 2
285/65R20 and the sizes next to it
To scale, on one ground line. Diameter by the formula.
Table 4
Compare 285/65R20 with another size
Type any size: diameter, sidewall, speedometer and clearance change against this one.
Comparison
275/65R20 is 34.07″ tall, −1.48% against 285/65R20. At 60 mph on the dial you drive 59.1 mph.
| Item | 285/65R20 | 275/65R20 | Change |
|---|---|---|---|
| Overall diameter | 34.59″ | 34.07″ | −0.51″ −1.48% |
| Section width | 11.22″ | 10.83″ | −0.39″ |
| Sidewall | 7.29″ | 7.04″ | −0.26″ |
| Circumference | 108.7″ | 107.0″ | −1.6″ |
| Revs per mile | 583 | 592 | +9 |
| Axle height | 17.29″ | 17.04″ | −0.26″ |
When the odometer counts 1,000 miles, you have driven 985.2 miles.
Engine RPM at the same road speed: +1.5%. Gear ratio calculator
Speedometer
| Dial shows | True speed | Difference |
|---|---|---|
| 30 mph | 29.6 mph | −0.4 |
| 45 mph | 44.3 mph | −0.7 |
| 60 mph | 59.1 mph | −0.9 |
| 70 mph | 69.0 mph | −1.0 |
| 80 mph | 78.8 mph | −1.2 |
285/65R20275/65R20
Note 1
P-metric or LT in the same size
9 LT and 0 P versions in the tables we read.
No single model in our tables is published in both P and LT versions of 285/65R20; Table 3 lists both types side by side.
On trucks and SUVs, the load ratings of the tires on an axle must add up to at least the axle’s GAWR on the certification label (49 CFR 571.110).
Vehicles on 285/65R20: not listed yet. We add a vehicle here only from its maker’s own spec sheet for that year and trim.
The size your vehicle left the factory on is printed on the tire and loading placard on the driver’s door jamb (49 CFR 571.110). Pressure and load: that placard too.
Table 5
Within 3% of 285/65R20
Same rim or ±1″, diameter within 3%. A shop rule of thumb, not a law.
| Size | Diameter | Width | vs 285/65R20 | At 60 mph | Clearance |
|---|---|---|---|---|---|
| 315/60R20 | 34.88″ | 12.4″ | +0.9% | 60.5 | +0.15″ |
| 35x11.50R20 | 35.00″ | 11.5″ | +1.2% | 60.7 | +0.21″ |
| 35x12.50R20 | 35.00″ | 12.5″ | +1.2% | 60.7 | +0.21″ |
| 35x13.50R20 | 35.00″ | 13.5″ | +1.2% | 60.7 | +0.21″ |
| 35x15.50R20 | 35.00″ | 15.5″ | +1.2% | 60.7 | +0.21″ |
| 295/65R20 | 35.10″ | 11.6″ | +1.5% | 60.9 | +0.26″ |
| 275/65R20 | 34.07″ | 10.8″ | −1.5% | 59.1 | −0.26″ |
| 34x11.50R20 | 34.00″ | 11.5″ | −1.7% | 59.0 | −0.29″ |
| 295/60R20 | 33.94″ | 11.6″ | −1.9% | 58.9 | −0.32″ |
| 325/60R20 | 35.35″ | 12.8″ | +2.2% | 61.3 | +0.38″ |
Q&A
Common questions
How many revolutions per mile does 285/65R20 make?
By the formula 285/65R20 makes 583 revolutions per mile (362 per km). Toyo lists 601 revs per mile for some models; maker tables may differ slightly.
What load range does 285/65R20 use?
Maker size tables list the 285/65R20 entries as LT tires with load range E. The tire sidewall shows the maximum load rating and, for LT tires, the load range letter (49 CFR 571.139).
Where do I find the vehicle's recommended pressure and load info?
See the tire and loading placard on the driver's door jamb for the vehicle maker’s recommended cold inflation pressures and loading limits (49 CFR 571.110).
Will my speedometer change with a different size?
Yes. A larger diameter raises the true speed relative to the indicated speed. Use the speedometer calculator or compare the neighbor numbers to estimate the change.
Notes
Method and sources
Each number and rule comes from a source with the date it was checked.
- Sidewall = width × aspect ratio ÷ 100
- Diameter = rim × 25.4 + 2 × sidewall (mm)
- Revs per mile = 63,360 ÷ (π × diameter, in)
- True speed = dial × new diameter ÷ old diameter
- Clearance change = half the diameter change
Numbers are nominal: the tire unloaded, on its measuring rim. Revs per mile published by makers run higher than the formula. “Within 3%” is a rule of thumb tire shops use, not a law. Tire pressure: the placard on your door jamb.
- Nitto: size table (nittotire.com)checked Oct 15, 2026
- Mickey Thompson: size table (mickeythompsontires.com)checked Oct 15, 2026
- Toyo: size table (toyotires.com)checked Oct 15, 2026
- 49 CFR 571.139 (FMVSS No. 139), S5.5(d)ecfr.gov · checked Oct 15, 2026
- 49 CFR 571.110 (FMVSS No. 110), S4.3ecfr.gov · checked Oct 15, 2026
Related
Calculators and size classes
- Tire size calculatorTwo sizes: diameter, sidewall, revs and speedometer.
- Compare up to 4 sizesUp to four sizes side by side, drawn to scale.
- Metric ↔ inchesMetric to inches, and 33x12.50R20 to metric.
- Speedometer errorTrue speed after a size change.
- Gear ratio and RPMEngine RPM and the ratio to regear to.
- Wheel offset and pokeBackspacing, poke and inner clearance.
- DOT date codeHow old a tire is, from the DOT number.
- Load index chartLoad index in pounds and kilograms.
- Bolt patternMeasure it, convert inches to mm.
- Rim size and tire fitWhat 17x8 ET35 means, which sizes go on it.
- What fits my carStart from the placard on the door.
- Tire size chartCommon sizes in inches, by rim.