Selecting a tire for the right application is important. If in doubt, check with your local tire retailer about the right application. Just like passenger cars and light trucks have different load ratings, so do commercial trucks. The correct tire size and load limits should be listed on the VIN decal on most autos and light trucks. In larger trucks they can be found in the glove compartment or the owner’s manual.
Also, think about where you’re traveling. A semi that drives the lower 48 on long hauls will require a different tire than a home heating oil delivery tanker truck in the northeast. Tread design, depth, and load rating are all affected by the application it’s designed to perform within. Chose the wrong tire for where, how, and what you’re hauling and you’ll likely spend more money in the end.
That’s why it’s important to note that LRR tires have an inherent design feature that helps reduce MPG while traveling. That feature is tread depth. Most new LRR tires have up to half the tread depth of a new conventional tire, and although the tire compound is designed for longer life, the trade off is you’ll still be replacing that tire sooner than a conventional tire.
For LRR tires, the reason behind less tread depth is that there is more tire surface to spread the ‘load’ of the weight the tire supports, which translates into less weight that tire bears on the tread that is contacting the road surface.
Also, tread depth increases the ‘squish’ factor on the tread. This explains why some conventional tires often have premature wear on the tread design and it becomes distorted as the tire wears, prompting premature replacement. To eliminate tread distortion from tire ‘squish’ simply chose a tread with less depth, or carry less weight.
Tire ‘squish’ also relates to tire ‘scrub’, a fuel mileage robber. Scrub is the action of the tread against the road surface. More scrub equals less MPG. Scrub also increases road noise from the tire and affect steering control in worse situations. It’s like riding a dirt bike with knobby tires on the pavement. This may help explain why on most OTR trucks the steering tires usually have a tread pattern that are linear in design, thus reducing road noise yet still providing good handling control in wet road conditions.
With any change in your fleet, simply conduct a test application with one or two of your units. Record all the cost factors associated with the switch, and watch the miles, wear, usability, and fuel. Make certain that your test accounts for the seasonal changes that might determine tire wear and traction equally and record the miles accurately with each fill up. Overall, the costs may not support the change to a LRR tire in light of lower fuel costs but it will help you determine what your price point is when fuel prices rise.