Try to distribute the weight as low as possible. Load somewhat lighter on your truck axles than on the trailer.
Dont forget to add actual weight of the trailer, trailer weight must be subtracted from gross to find allowable load on trailer. This goes the same for your truck.
Gvwr minus Net Weight = Maximum allowable load
We are short a few variables to complete your equation. How many pallets would be the biggest question? And my little formula only works for truck or trailer alone, not both.
Something else I would be concerned about. I assume this is a wooden deck on your trailer? Your pressure per square inch is very high and it would be very likely your pallets can sink right through a less than sturdy trailer deck. At 2K per pallet make dang sure you line those pallets up with the steel cross braces of your trailer for support. You might even consider using an extra layer of plywood (nailed down) to help evenly distrubute your load.