2008 Acura MDX — Base Model
The 2008 Acura MDX Base Model shipped with 2 different factory tire sizes, depending on the wheel package it left the factory with (this can also reflect a staggered front/rear setup). Check your tire sidewall or door placard to confirm which one applies to your vehicle.
This trim shipped with more than one tire size (staggered fitment, front/rear, or optional wheel package). Confirm which one matches your vehicle by checking your tire sidewall or door placard.
255/55R18
| Section width | 255 mm |
|---|---|
| Aspect ratio (sidewall height) | 55% (140.3 mm) |
| Rim diameter | 18" |
| Overall tire diameter | ~29" |
| Revolutions per mile | ~694 |
Compare prices at:
275/45R19
| Section width | 275 mm |
|---|---|
| Aspect ratio (sidewall height) | 45% (123.8 mm) |
| Rim diameter | 19" |
| Overall tire diameter | ~28.7" |
| Revolutions per mile | ~702 |
Compare prices at:
What this size means for your Acura MDX
On the 2008 Acura MDX Base Model, the factory 255/55R18 measures about 29″ in overall diameter with a 140.3 mm (5.5″) sidewall, and completes roughly 694 revolutions per mile. Its 55-series aspect ratio gives a balanced everyday-passenger profile — enough sidewall to soak up road shock while keeping steering response crisp. In tire terms it is a passenger (P-metric / Euro-metric) size.
The 255/55R18 and 275/45R19 roll within 0.3″ (1%) of each other in overall diameter, so they are interchangeable from a speedometer standpoint — the second size is an optional wheel package rather than a different rolling size.
On a vehicle of this age, the Acura MDX may have been refitted with a slightly different replacement size somewhere in its life, so check the current sidewall — not just the factory spec — before buying.
Acura MDX tire sizes by year
- 2026 Acura MDX 255/50R20
- 2025 Acura MDX 255/50R20
- 2024 Acura MDX 255/50R20
- 2023 Acura MDX 255/50R20
- 2022 Acura MDX 255/50R20
- 2020 Acura MDX 265/45R20
- 2019 Acura MDX 265/45R20
- 2018 Acura MDX 245/60R18 / 245/50R20
- 2017 Acura MDX 245/60R18 / 245/50R20
- 2016 Acura MDX 245/60R18 / 245/55R19
How to read a tire size
A tire size like 225/45R17 breaks down into three parts:
the first number is the section width in millimeters
(the tire's width from sidewall to sidewall), the second is the
aspect ratio — the sidewall's height as a percentage of
that width — and the number after the "R" is the rim
diameter in inches. A letter prefix (P or LT) indicates
Passenger or Light Truck construction; its absence usually means
Euro-metric sizing.
Some trucks and off-road tires instead use "flotation" sizing, like
37X12.50R17 — here the numbers are the tire's overall
diameter and width in inches directly, with the rim diameter last.
Always verify against the tire information placard on your driver's-side door jamb or your owner's manual before purchasing — tire size can vary by factory option package even within the same trim.