Fundamentals
Cracking the Code: Tire & Wheel Sizing Explained Simply
A beginner-friendly breakdown of what numbers like 245/40 R18 actually mean for your vehicle.
Advertisement
Sponsor / Mobile Banner Ad
Configuration
OEM Specification
Replacement Setup
Cross-Section Analysis
Suspension Risk
Fender Risk
Diameter Comparison
Diff: 27.8mm (4.4%)
Speedo: +4.4%
Strut Gap
-3.7mm
Fender Poke
+16.4mm
Ground Clear.
+13.9mm
Speedo @ 60
62.6mph
Safety Assessment
- WARNING: ABS/ESP Failure Risk. Speedometer variance exceeds safety threshold.
Quick Guide
1
Look for numbers like 245/40 R18 on your tire's sidewall.
2
Enter these in the OEM Specification section.
3
Compare with your new tire size to see if it fits safely.
Advertisement
Featured Sponsor Space (300x250)
Calculations are theoretical estimates based on standard tire physics models. Always verify with physical measurements before high-speed operation.