HTR Z5

About the Sumitomo HTR Z5

Summer Ultra High Performance Passenger Car tire.

Features

* Advanced tread compound* Wide circumferential grooves* Optimized tread rigidity* More than 50 sizes, from 17”- 20”, in Y speed ratings* Free Defect Replacement for Life of Usable Tread

Benefits

* Enables quick and powerful wet braking* Enhance wet road traction and boost hydroplaning resistance* Provides predictable high-speed stability* Excellent segment coverage

Understanding the 245/40ZR18 XL size

In the size code 245/40R18, 245 is the section width in millimetres (about 9.6"). 40 is the aspect ratio — the sidewall height is 40% of the width, or roughly 98 mm. R18 means radial construction on a 18-inch wheel, giving an approximate overall diameter of 25.7".

The load index 97 means each tire supports up to 1,609 lbs — about 6,436 lbs across a full set of four. The speed symbol Y certifies the tire to 186 mph under its rated load. Always match or exceed the load index and speed rating listed on your vehicle's door-jamb placard.

Tread life and grip ratings

This tire carries a UTQG rating of 320 AA A. The treadwear grade of 320 is a relative durability score — a grade of 200 is expected to last roughly twice as long as a grade of 100 under the same controlled test. Traction grade AA measures straight-line wet stopping grip (AA is highest, then A, B and C). Temperature grade A reflects heat resistance at sustained speed (A is highest).

Price and value

At $128.99 per tire, a full set of four costs $515.96. That is about 24% below the average price of the 127 tires we stock in this size.