LT stands for “Light Truck.” A tire with this symbol on the sidewalls is basically telling you that it’s designed for use on trucks, vans, and full sized SUVs, basically vehicles with heavier weight (with a payload of 1 ton or less). So since LT sizes are able to carry more weight, they are also rated with higher load ratings.
Basically there are two types of tire sizes, one is P metric, which are made for “passenger” tires and they don’t have to carry a lot of weight, while the other is LT, which are mostly seen on off-road tires, and these tires can go on aggressive terrains and have the capability to tow.
So if you have a full sized SUV, it’s best you replace the tires with LT. P-metric to LT is acceptable, but never replace original equipment LT tires with P-metric tires as they can’t bear the load capacity at maximum pressure.
Learn all about load ratings here.
LT vs P Metric
Although a tire can have similar inner construction, of polyester casing, steel belts and nylon cap plies, on LT sizes they are thicker and are composed of stronger cords allowing them to have enhanced durability over P metric sizes.
Though the extra materiel in the internal plies do get to increase the overall weight of the tire, and with that they are not able to provide similar performance on roads.
And this brings us to pros and cons of both metrics.
Advantage of LT over P Metric
Let’s start with the advantages you get with these tires over non-LT sizes.
Increased load capacity
LT Tires are designed to carry a higher load than P-metric Tires. They have a stronger construction and reinforced sidewalls that allow them to support a higher weight than P-metric Tires.
This makes them a good choice for heavy-duty vehicles such as SUVs, vans, and pickups.
Enhanced durability
Durability is the main one with these, as with heavier ply construction, they get to be more puncture resistant compared to non-LT or P metric sizes.
These tires basically have a reinforced construction, which means they can withstand more pressure and stress in comparison. So with that, these tires give you a extended lifespan if you are running heavier loads.
Greater safety
Carrying heavy load, one needs to assure there won’t be any risk of failure.
With non-LT sizes, you can’t have that kind of surety if you have to carry heavy loads, and this compromises on the overall safety.
Improved off-road performance
Compared to P metric tires, LT tires usually have deeper grooves, and a slightly balder design which provide superior self cleaning especially on muddy and gravely roads.
The thicker lugs also help out in sticking on to the rocks with wider groove mouth, providing crawling bite in all directions.
And since these tires are more powerful, they are able to climb rocks, take on muddy terrains, going on sandy dunes, basically all those areas where you can never go with a P metric size (at least its not recommended that you do, if you love your tires).
Moreover, with a stronger bead construction, these tires allow for lowering of air pressure in a better way which provides amazing traction values on soft sand.
Enhanced stability
Compared to P metric tires, LT tires have a larger contact patch, which provides better stability and this goes especially when you are running with a heavier load/cargo.
Moreover, with stiffer sides, they give you a crisp handling overall, that’s because during cornering the tire’s sidewalls and shoulders come in to action, making a more solid connection with the road.
A P metric tire with heavier weight would simply form a bulge which would be bouncy while taking turns.
Disadvantages of LT Sizes
They are expensive
Since LT tires have thicker plies in their internal construction, they are manufactured with more resources and so compared to P metric, they get to be costly.
These tires also (mostly) have more tread depth, and a composition of higher Kevlar compounds, and both of these things further add to the over cost.
Tread life
Tread life of LT tires is never better compared to P metric, as having extra reinforcing materials in their construction, the tread bears more pressure and rubs off the surface with larger force.
That’s why you on a same tire you often get (10K miles) better wear warranty on P metric sizes compared to LT.
Recommended: How To Increase Tread Life?
Ride comfort
Ride comfort depends on two main things, on road vibrations, and tread noise, and LT tires aren’t better in both these areas.
Their stiffer sidewalls which made to support the heavier loads and rougher terrains aren’t able to absorb the bumps smoothly on paved roads.
These rigid sides also account for larger air travel through the shoulders, which then hits around causing more noise.
P metric tires on the are smoother, and air particles aren’t able to come in with as much frequency.
Fuel efficiency
I bet you saw this one coming. LT tires simply lowers your fuel economy on paved roads. So if you are using these tires as your daily driver, make sure you ready for frequent trips to gas stations.
With heavier weight, more pressure in emphasized on the lugs, and as a result during acceleration and handling, they tend to flex more.
With this excessive bending of the tread blocks, energy is consumed, which could have otherwise used in to rolling the tire.
LT Tires may not be compatible with the vehicle’s tire pressure monitoring system (TPMS), which can cause safety and performance issues. This is because the TPMS is calibrated for P-metric tires, which may not be able to accurately measure the pressure and temperature on LT Tires.
Conclusion
So basically Light Truck (LT) tires are made for carrying higher load and handle rougher terrains compared to P metric sizes. That’s why these tires are ideal for heavy-duty vehicles such as SUVs, vans, and pickups.
Their reinforced sidewalls can handle additional stress of off-road driving and with a larger contact patch (carrying heavier weight), they provide the needed stability and along with it safety.
Though keep in mind, that these tires are not as budget friendly in comparison, and speaking of which, with them you also spend more on fuel, as they generate larger rolling resistance values.
