Tires have two lifespans and whichever runs out first is the one that matters.
Tread life, by type
| Type | Typical life |
|---|---|
| Touring all-season | 50,000–80,000 miles |
| Standard all-season | 40,000–65,000 |
| Grand touring | 45,000–70,000 |
| Performance all-season | 35,000–55,000 |
| Summer performance | 20,000–35,000 |
| Winter | 25,000–40,000 (winter use only) |
| Light truck all-terrain | 40,000–60,000 |
Treadwear warranties are usually optimistic against real conditions, and they are prorated: a claim at half the warranted mileage returns roughly half the price, not a new tire.
Calendar life: 6 to 10 years
Rubber oxidises and the compound hardens whether the tire rolls or not. Most manufacturers recommend replacement at 6 to 10 years from the date code; many vehicle makers say 6 regardless of tread.
That is why the DOT date code matters at purchase. "New" tires sold from old stock are common, and a tire made four years ago has spent much of its calendar life on a shelf.
Spare tires die this way almost universally — full tread, twelve years old, and not safe to drive on.
What actually determines wear rate
Alignment. Toe misalignment is the fastest tread destroyer there is and it is nearly invisible. Get an alignment with new tires.
Pressure. Both under and over shorten life, in different patterns. Check cold, monthly.
Rotation. Every 5,000 to 8,000 miles typically adds 20% to set life, because front and rear wear differently.
Driving. Hard cornering, hard braking and hard acceleration all wear tread, and heat accelerates every degradation mechanism. Aggressive driving can halve tread life.
Compound. A softer, grippier compound wears faster. That is a design decision, not a defect, and it is why UTQG treadwear and grip run opposite each other.
The depths that matter
- 10/32 in — most new passenger tires
- 6/32 — snow traction has already fallen off; replace winter tires here
- 4/32 — wet stopping distance is degrading measurably. The practical replacement point
- 2/32 — legal minimum in most of the US, and well past useful. Wet braking at 2/32 is dramatically worse than at 4/32
A quarter inserted into a groove finds 4/32. A penny finds 2/32. The quarter is the more useful coin.
When to replace early regardless
Sidewall bulges or cuts, tread separation, repeated slow leaks, cords showing anywhere, or an impact hard enough to bend a rim. None of those are wear questions, and none of them get better.