Tire Guide Cheat Sheet

Last Updated: November 21, 2025

Reading Tire Size

P215/65R15
P=Passenger, 215=width(mm), 65=aspect ratio, R=Radial, 15=diameter
Load Index
Max weight tire can carry
Speed Rating
Max safe speed (H=130mph, V=149mph)

Tire Pressure

Check monthly
When tires are cold
Find PSI
Door jamb sticker or manual
Underinflated
Poor fuel economy, wear
Overinflated
Rough ride, center wear

Tread Depth

Penny test
Lincoln's head upside down
2/32 inch
Minimum legal tread
Replace at 4/32
Safer in rain/snow
💡 Pro Tip: Rotate tires every 5,000-7,500 miles!
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