You need to tell us what truck you have. Also what is the GVW on the truck as posted either on the door or elsewhere.

My 3500 is Rated for 38,100 lbs Gross Combined, Truck and Trailer. The GVW for the truck is 14,000 lbs. That means the max weight the truck can carry in the truck, which includes, passengers, tool boxes, fuel, other normally carried including the bed rails and hitch or the hitch if bed rails are not needed.

My truck is 9840lbs with the hitch, bed rails, Aux fuel tank + 75 gallons of fuel and a full tank in the truck. That means to stay within the factory ratings my pin weight on the hitch can’t be more than 4160 lbs. I am over that figure by about 340 lbs with the full Aux fuel tank or the trailer pin weight which is close to 4500 lbs. it Varys a little.

So, you need to go get weighed with a full tank of fuel and whatever else you carry when towing and subtract the truck weight from your trucks GVW to figure what’s left for pin weight in the truck from the trailer.

If you known what your loaded trailer weight, use 20% of that weight to figure pin weight so you can size the fifth wheel hitch size. That would be both the vertical weight on the hitch plus the pulling rate. Get something bigger so you got room.

Go go to the scale with the trailer use a 3 Pad scale.

After weighing, subtract the drive axle weight without the trailer from the drive axle weight with the trailer. That would be your pin weight.

Now check the front and rear axle ratings and compare the weights recorded when weighed with the trailer. Make sure your not over the ratings. You should be ok.

Hope this helps.

Feel free to ask questions.

Dave