HT, AT, MT… What do you really need ?
When you’re outfitting your trucks with new tires, what should you be getting? It’s best to work with your tire supplier to determine what’s appropriate for your needs and budget.
The first question is whether to choose a light truck (LT-Metric) or passenger (P-Metric) tire. It might seem straightforward to put a truck tire on a truck, but some automakers equip their vehicles with P-Met tires, since they’ll primarily be used by consumers. P-Met are usually less expensive as well. But where it can really get confusing is that some P-Met tires sized to fit a light truck may have a maximum load rating that’s higher than an LT-Met tire of the same size.
Handling maximum loads
Still, you should stick with the truck tire. According to Greg Cressman, Director of Technical Services Department at Yokohama Canada, the P-Met tire’s maximum rating is only for occasional heavier-duty work. LT-Met tires are engineered to handle their maximum rated loads all the time.
“You’d think truck tires would have a higher capacity, but there’s a presumption that it will have a harder life, while the passenger tire will have an easier life,” he says. “It’ll be going to the office, to the coffee shop, usually with only one person, whereas the light truck tire can be working for a living eight hours a day. The best interpretation of the logic is that the light truck tire will be working harder, so they de-rate it to make sure it can survive.”
Check your pressure
The P-Met tire will usually have a lower pressure recommendation than an LT-Met tire of the same size, and if you do switch from one to the other—in either direction— your door label should be adjusted to reflect the correct pressure.
For vehicles that go off the beaten path, such as into muddy job sites or unassumed roads, off-road tires may be a consideration. Tires are divided into HT (highway terrain), AT (all terrain), or MT (mud terrain). All have pros and cons, and since stepping up between them means moving up to a more capable off-road tire—and usually with a heftier price tag—it’s important to realistically assess the duties your fleet does.
Pros and cons
Most light-duty trucks with LT tires are delivered with the highway terrain variety. They offer longer lifespans, a quiet ride, good fuel economy, and a straighter tread pattern for predictable handling on asphalt. Still, they can often be more capable than you might expect on many off-road surfaces—and, as well, many people overestimate just how nasty the terrain is where they’ll be driving.
All-terrain tires have a more aggressive tread for better grip in muddy conditions, and for those who send their fleets into the rough stuff, these may be the best tire for the job. However, be aware that some can give you a noisy ride on pavement. They also might not last as long as an HT tire, and since they’re more likely to wear unevenly, they need to be rotated more often.
Mud terrain tires are the tough stuff, and it’s very unlikely you’ll be looking at them. They’re very specialized and are generally used primarily by off-road enthusiasts. They’re usually noisy and can be hard to balance, and really don’t have a place in fleets, other than those that work in very extreme conditions.