Hitch Weight Question

[mojo]

Here's how I did it, resting the Hensley on the scale closest to the stinger. Moving the scale back and under the jack stand post showed an additional 200 lbs.

[withidl]

I'm probably opening myself up to severe criticism for the following, but for what it's worth, the tongue weight being ~10-12% of the AS is not as critical when using a Hensley type hitch interface.

Yes it is ideal to be ~10-12%, but the Hensley type interface through its geometric anti-sway control allows for tongue weights somewhat beyond those of standard tongue on ball hitches.

[mojo]

Agreed.

But it's still nice to know what the actual dead weight is on the vehicle hitch prior to tightening.

[dkottum]

Originally Posted by mojo

Here's how I did it, resting the Hensley on the scale closest to the stinger. Moving the scale back and under the jack stand post showed an additional 200 lbs.

Good post mojo. The difference is very interesting.

doug k

[SteveSueMac]

Originally Posted by mojo

Here's how I did it, resting the Hensley on the scale closest to the stinger. Moving the scale back and under the jack stand post showed an additional 200 lbs.

I think that's the right location for a vpp hitch. Back at the jack stand isn't. I did a procedure on the scales but am now thinking about investing in a Sherline :-)

Thanks for the photo!

[Ron Gratz]

Assuming the trailer remains at the same "level" (parallel to the pavement) attitude --

the difference between "tongue weight" measured under the tongue jack and the weight measured at some other point depends on 1) the distance between the jack and the other point and 2) the distance from the jack to the midpoint between the axles.

For example, if the distance from jack to axles is 200" and the distance from jack to other measurement point is 20" (assumed for PP),
the ratio of load measured 20" ahead of jack to load measured at the jack would be 200/(200+20) = 91%.

For these dimensions, if the load measured at the jack is 1000#, the load measured 20" ahead of the jack should be about 910#.

Ron

[dkottum]

This difference in tongue weight relative to the distance measured from the trailer axles was discussed briefly in an earlier thread. I am glad to see mojo post some true numbers, and thanks to Ron Gratz for his usual math genius.

So, many of us just add the trailer tongue weight (measured at the coupler) and the weight of the w.d. hitch together to determine the tongue weight put on the truck receiver.

But because of the added distance from the trailer axle of Hensley/Propride, the actual weight put on the truck receiver is less, as I understand it.

Or, my Propride weighs 225 lbs and my Airstream tongue weight is 875 lbs, totaling 1100 lbs. The weight supported by my truck receiver is actually less than 1100 lbs, because of the added length of the Propride. Yes or no?

doug k

[switz]

Post #4 was very informative about the owner's trailer axle's load per axle.

The Airstream parts manual for the 2013 Classics shows that the axle used for both the 27' & 31' models are rated at 5,000 pounds ( the label on the side of the trailer may reflect a different number).

Thus the front axle in the post was actually overloaded if the axles of that particular trailer are actually rated 5,000 pounds. If the poster is using GYM ST D rated tires, they are rated for 2,540 pounds each or 5,080 pounds on the axle.

Thus one could logically expect that the overloaded front tires might be more subject to failure than the rear tires carrying less than their rated load.

The next step would be to weigh each tire position at the same time to check tire loading side to side.

YMMV