C on a tire: C (commercial or van)
A commercial van tire. The C sits after the rim diameter, not before the width.
What it changes
195R14C and 195/70R15C are commercial van sizes. The C is easy to miss and easy to confuse with a load range C, which is a different marking in a different place. A van rated for a C size is not adequately shod with the same numbers in a passenger construction.
Where it sits: After the rim diameter, at the end of the size.
The other prefixes
The prefix decides which load table rates the tire, so the same numbers after it do not mean the same capacity.
- P-metric (passenger) - A passenger car tire rated against the North American Tire and Rim Association tables.
- Euro-metric (no prefix) - No letter at all. The tire is rated against the European tyre and rim organisation tables.
- LT-metric (light truck) - Built for light truck duty, and rated for it without any derating.
- ST (special trailer) - For trailer axles only. Not for a vehicle that steers or drives.
- T (temporary spare) - The space saver spare. Restricted speed and restricted distance.
Questions
- What does C mean on a tire?
- A commercial van tire. The C sits after the rim diameter, not before the width. 195R14C and 195/70R15C are commercial van sizes. The C is easy to miss and easy to confuse with a load range C, which is a different marking in a different place. A van rated for a C size is not adequately shod with the same numbers in a passenger construction.
- Where does the C appear on the sidewall?
- After the rim diameter, at the end of the size.
- Does a C tire take the 1.10 light truck derating?
- No. The 1.10 factor applies to P-metric and Euro-metric tires fitted to a light truck. It is not the rating scheme this type is rated under.
Where these figures come from
Published values here were read from 2 independent sources:
- Tire code - Wikipedia, revision read 27 August 2026 (read 2026-08-27)Service type letters, construction letters, load range letters and ply ratings, sidewall marking glossary
- Load Index & Weight Ratings - rimlist, undated reference article (read 2026-08-27)LT against P-metric fitment, ST trailer tires, SL, XL and HL reference pressures
These are independent publishers, not independent measurements. Each one reproduces a table originally set by a standards body, so agreement between them shows a value was transcribed correctly, not that the underlying table is right. Where a figure is safety relevant, check it against the tire manufacturer's own data before relying on it.