Weight Distribution %

[gunter]

Has anyone set up their weight distribution hitch such that there is no change in the % of weight over each axel - each axel needs to stay under the GAWR of 1290 kgs/2,838 lbs:

Sienna - both axels - no trailer = 4,497 lbs = 100%
Sienna - front axel - no trailer = 2,535 lbs = 56%
Sienna - rear axel - no trailer = 1,940 lbs = 44%

i.e. set up the weight distribution hitch to achieve the following:

Sienna - both axels - trailer hooked up = 4,928 lbs = 100%
Sienna - front axel - trailer hooked up = 2,760 lbs = 56%
Sienna - rear axel - trailer hooked up = 2,168 lbs = 44%

Any and all thoughts/comments would be greatly appreciated.

Thank you.

Gunter

[brian_bp]

I understand the intent, and it should in general be possible to push the distribution forward with the WD system to offset the rearward effect of the trailers tongue weight to get this, but I don't think it makes physical sense to do it.

The load on an axle determines the traction available to each tire, and that should be distributed to match the distribution of the mass. If the traction and mass distribution don't match, when the vehicle needs lateral force (to turn a corner) the force will tend to spin or jacknife the rig... like pushing on one side of a box sitting on ice, instead of pushing it in the middle. This is why even WD system manufacturers warn against over-applying the system.

There's a reason that the front-heavy Sienna has just as much load capacity in the rear axle: that's where the payload is carried. There's nothing wrong with the vehicle's weight - and axle load - distribution becoming more rear-biased with increased load; I would be comfortable with 50/50 or even moderately rear-heavy. I especially want that load on the rear axle - and the resulting traction - when there's a trailer to be controlled.

[gunter]

Good points. Initally I thought my idea made sense. But after reading your comments, I don't think it was such a great idea.