Tire Tread Wear and Remaining Life in km
Enter the current tread depth, the minimum you accept and the wear per 10,000 km to get the distance left. 5 mm, 1.6 mm and 1 mm give 34,000 km.
Km restantes
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Tire wear and remaining life
To find how many km a tire has left, use remaining_km = ((tread_now − tread_min) / wear_per_10k) · 10000. In Brazil the legal minimum tread depth is 1.6 mm, which you can spot from the TWI (Tread Wear Indicator) bars molded into the grooves. A typical passenger tire goes 40,000–80,000 km. There's also the UTQG Treadwear rating (US spec), which takes 100 as its baseline, so a tire rated 400 lasts about 4× as long. Example: 5 mm current, 1.6 mm minimum, 1 mm wear per 10,000 km → (5 − 1.6)/1 · 10000 = 34,000 km remaining. Drive hard or run with bad alignment and you can accelerate wear by 30%.
Maintenance and applications
Rotate every 10,000 km so the front and rear axles wear at a similar rate. Swap tires out after 4–5 years even when the tread looks fine, because the rubber dries out and cracks. People reach for this when doing maintenance planning, tracking cost-per-km KPIs across delivery and fleet operations, or running a brand comparison between Michelin, Pirelli, Goodyear and Continental. Running 20% underinflated pushes wear up 25% and fuel consumption up 4%.
FAQ
How do I measure tread depth? A tread depth gauge (a cheap caliper does the job) works, or just use a R$ 1 coin. If the edge disappears below the rim, you're already under 2 mm.
Why does alignment matter so much? When the wheels are out of true, one edge of the tire drags sideways with every meter you drive. A few degrees off is enough to wear a tire out 30% faster.
Can I replace just one tire? You can, but you're better off doing them in pairs on the same axle so grip stays balanced. When grip is uneven, the wet brings nasty oversteer or understeer surprises.
Old tire with high tread, still safe? No. Past 5 years the rubber compound hardens and loses grip no matter how much tread is left. Check the DOT code (week/year) on the sidewall to see its age.
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The results provided by this tool are for general informational and educational purposes only and do not constitute professional, financial, medical, legal, tax or accounting advice. Always confirm important decisions with a qualified professional and official sources.