GVWR Calculation Question

Omodan wrote:
So I hitch my trailer tongue to the rear of my vehicle. That increases the load on my rear axle. Since I have a WDH, that pushes that weight further down my frame to my front axle, and a little to my trailer axles. Now if I adjust my WDH such that the weight applied to my front axle is the same as prehitched, then the weight is pushed back to my rear axle once again. However, the weight applied to my rear axle can only get as heavy as my front axle before it begins to affect the front axle once again. The weight applied to my rear axle above the weight already placed on the front axle is then forced to the trailer axles...

To make the arithmetic simple -- let's assume a tongue weight of 1000#, wheelbase of 130", ball overhang of 65" and ball to TT axle distance of 195".
The 1000# TW would cause 500# to be removed from the TV's front axle.
The WDH could be adjusted to add 500# back onto the front axle giving a net load change of zero.

The 1000# TW would cause 1500# to be added to the rear axle.
Adjusting the WDH to return 500# to the front axle would cause 750# to be removed from the rear axle.
The net load change on the rear axle would be 1500-750 = 750#.

Adjusting the WDH to add 500# to the front axle would cause 250# to be added to the TT's axles.

The net load changes for front, rear, and TT axles would be 0#, 750#, and 250#.

If I'm not just completely off, then my rear axle weight will increase to 3580 as well. This will result in a GVW of 7160, 60 above my max. The rest of the ~1000 hitch weight will then be added to the trailer axles. So in my theory, I need to have the front axle no more than 3550, use a WDH, and ensure the remaining weight pushed to the trailer doesn't exceed its GVWR, my tow capacity or the combined GVWR...

If your unhitched weight is front=3580# and rear=2680#, and the tongue weight is 1000# -- you could adjust the WDH to keep the front at 3580 and the rear would increase to about 3430#, with 250# being added to the TT's axles.

The actual changes would depend on your values of wheelbase, ball overhang, and distance from ball to TT's axles.

Ron