A P-metric or metric tire is one made especially for passenger cars, some SUVs, some light trucks, and crossovers. On the other hand, an LT tire is one made, especially for light trucks. This type of tire is usually able to carry higher loads than the P metric tire.
When you want to replace a tire on any light truck, you must see to it that the size and load range will allow equal or even higher carrying capacity. LT tires need higher air pressure to carry loads equivalent to metric tires.