gross weight rating and axles strength

How do you get a gross trailer weight rating of 21,000lbs when you have three 6,000lb axles underneath the camper?

Something doesn't add up in my head. I have been trying to figure out if it had anything to do with the expected amount of pin weight that may be taken off the axles by the truck but that is the only thing I can think of.

Thanks,
Chris

Pin weight ~ 3,000#.
The axles and the two legs at the front support your trailer.

My 3795 on only rated at 18,000/ with #3, 6,000lb axles

My gross is listed as 20,400lbs per the sticker. I was just trying to figure out how that worked out with only 6,000lb axles. I guess the pin and jacks take some weight off of them but there isn't a lot of room to spare there.

Thanks,
Chris

Luckyhat12 said:

...the pin and jacks take some weight off of them but there isn't a lot of room to spare there.

Click to expand...

Why would you expect spare room in the rating? The numbers add up to the numbers, the safety factors are in there for sure. FW numbers are a lot easier to understand than truck numbers.

btw - my 6000# axles are carried by a pair of 3520# tires, so there's margin there... I run well below my gross anyway which gives me additional margin on tires, braking and the kingpin.