Product Knowledge: The LT Question


The 2015 Chevrolet Silverado 3500 HD
(Photo: Chevrolet)

Some SUVs and pickups can be fitted with either LT or passenger type tires… but recommending the non-OE tire is a tricky business.

Crossovers, SUVs and pickup trucks continue to climb the sales charts, while passenger cars slide the other way. Some crossovers have upped the off-road quotient the same time that pickups have upped the on-road comfort quotient.

Tire companies have responded with expanded product lines to fit this newish breed of vehicles that straddle the car-truck boundary, and continue to design and sell them in three classifications — Euro-metric, P-metric, and LT.

Dan Wysocki, who looks after tire fitment and validation for Fiat Chrysler Automobiles (FCA), says one way of simplifying the light truck tire landscape is to simply refer to both the Euro-metric and the P-metric tires as “passenger car” tires. “They are basically the same tire, a passenger car type tire,” says Wysocki

Euro-metric, which is also known as Hard-metric, was originally fitted exclusively to European imports, but now that the auto industry is globalized, P-metric and Euro-metric have come to coexist peacefully here in North America.

But as tire professionals know, the difference is quite vast, when you compare a passenger car tire and an LT (Light Tuck) tire. The LT tire features more robust construction, enabling it to survive in off-road conditions, and to shoulder heavier loads.

Higher pressures are ultimately what allow the LT to shoulder the heavier loads. Wysocki notes that LT tires designated with C, D, and E load ranges, run pressures of 50, 65 and 85 psi respectively, while passengers cars are typically inflated up to 35 psi.

“The LT tire is an entirely different animal,” says Wysocki.

More options, more questions from SUV customers

“On a weekly basis I will have customers question the durability of the passenger type tire on their SUV,” says Paul McAlduff, who owns and operates, Tireland Performance Centre, in North Vancouver, B.C.

He notes it happens more with owners of traditional, truck-based SUVs, but crossover owners also do their share of second-guessing. Recently he helped a customer with a Kia Sorento find happiness with a set of Michelin Latitude Tour tires, which are more SUV focused than other options which have now become available, as almost all tire lines expand to include more SUV and crossover sizes.

An LT tire is not even an option for the vast majority of crossovers, SUVs and pickups, says McAlduff. The first and obvious clue is whether or not the vehicle was originally equipped with LT tires. If it wasn’t, you should stay with passenger type tires.

“If a customer is leaning toward switching to an LT tire,” McAlduff adds, “they may be intending to use the vehicle in a way that is a step above what the manufacturer designed it for…” Clearly that’s trouble, if a customer intends to load up a vehicle over its GVWR, or go hard-core off-road when it wasn’t designed for it.

Not only is the vehicle over its head, the LT tires present all sorts of compatibility issues. “We design and engineer the vehicle for that size tire, and we recommend that you replace it with the OE tires,” says Wysocki. “The tire (pressure and load) information located on your tire placard, correlates only to the tire that is equipped on that vehicle. It doesn’t correlate to an LT tire that you might want to put on there.”

In addition to issues with tire pressures and whether they physically fit or not, the heavier LT tire may adversely affect the handling and durability of the vehicle’s steering and suspension components, which were optimized for the lighter passenger car tire. Wysocki notes that they would also not be compatible with the vehicle’s electronic stability control, and tire monitoring systems, which are set for the lower pressures. The vehicle’s warranty could also be in question, if problems arise when it is run with non-OE specification tires.

There are also speed ratings to keep in mind.

When pickups and SUVs straddle the LT line

For slightly older vehicles without all the sensors, and with vehicles that are originally and/or subsequently beefed up enough to handle the heavier LT tire, the LT might indeed be the right upgrade.

“We sell plenty of LT tires going on a vehicle that came with P-metric fitment,” says Steven Peters, Country Marketing Manager, Michelin Brand Light Truck, Greenville, South Carolina.

He notes that most 1500 series pickups come with passenger tires, while the heavier duty 2500 and 3500 pickups are always fitted with LT tires. Consider the Ram 3500 with 6.4-litre Hemi V8 and dual rear tires — the weight of the truck itself is 7,390 pounds! That’s a truck that needs high-pressure LT tires.

Peters says some 1500-series pickup users, and obviously any serious off-roader, simply need the more durable LT tire, because they operate in rough, non-pavement areas that can easily cut up a passenger type tire.

McAlduff notes that an owner of a large, truck-based SUV, which is towing close to its maximum load, might appreciate the extra lateral stiffness of an LT tire, and its ability to mitigate trailer sway.

But Peters reminds us once again, that it’s usually preferable to stay with the OE tire, even on a fully maxed out, truck-based SUV. “You can certainly step up to an LT, but again it comes down to the capacity of that vehicle. If a Tahoe, for example, is loaded down with people and their camping equipment, and is towing a boat, and it is still below the limit of what those tires can do, then it is still within the window of what that vehicle was designed to handle.”

FCA’s Dan Wysocki also cautions pickup and SUV owners eying aftermarket 20-inch rims. Such wheels and tires will actually “decrease” their vehicle’s overall carrying capacity. “With the wheel getting bigger, the tire gets smaller, so you’re going to get less air into that tire. A smaller sidewall (and less air) will get you less load carrying capacity.”

Ask the right questions

Regardless of which type of tire — passenger or LT — ends up on your customer’s vehicle, the decision process starts the same way — with questions.

“The best route is to truly understand the customer’s needs and wants,” notes Michael Minialoff, Senior Category Business Manager of Tire, Wheels and Accessories, Canadian Tire. “And that comes from asking the right questions. We have to remember that we talk tires all day long, but for our customers it may be a topic that only comes up every few years. We make sure that every customer will be satisfied with that tire for its entire life, and that comes from the conversations leading up to the purchase.”

Share it !