LarryJM wrote:
The problem with what you are now saying is that you have already conceeded that applying extra cargo wt aft of the TV rear axle, a portion of that will show up as an additional wt. on the TT axles.---
Larry, it's not a "concession". It's a simple fact of physics.
LarryJM wrote:
---Having extra wt show up on the TT axles w/o physically adding any wt to the TT can only come from what we typically classify as tongue wt that is being redistributed by the WDH to the various axles.---
Having "extra wt show up on the TT axles w/o physically adding any wt to the TT" results from torque which is applied to the hitch head by the WDH bars. It does not come from a redistribution of "tongue weight".
A WDH doesn't redistribute "tongue weight" -- it redistributes reaction forces acting on the TV's front axle, the TV's rear axle, and the TT's axle(s).
In fact, you could set up a TT to have ZERO tongue weight and the WDH still could redistribute axle reaction forces.
The WDH removes load from the TV's rear axle and distributes that removed load to the TV's front axle and the TT's axle(s).
LarryJM wrote:
---Let's say that extra 50lbs you have used is because of an extra 200lbs applied on the rear bumper of the TV then just where does the other 150lbs show up axle wise. If some shows up on the rear axle and some on the front axle of the TV as I believe it will then that can be only attributed to 200lbs added tongue wt. that has now been redistributed in those amount among the three axles (taken say all axles on the trailer as one wt.)
In other words please explain how that extra 50lbs you have mentioned gets transferred to the TT axles by adding wt at the rear of the TV back axle.
As stated before -- there is no actual weight (mass) added to the TT.
When the rear of the TV is pushed down, the WD bars produce a torque which causes increased upward force (50# for this example) on the TT's axle(s).
A simple free body diagram will show that the upward force of 50# acting on the TT's axle(s) will cause the downward force on the hitch/receiver to be reduced by 50# (in accordance with conservation of mass).
LarryJM wrote:
Again, while you can disagree with what are considered other experts one such from a source that should have some credibility is etrailer and in THIS LINK this cargo is explained and attributed to tongue wt. Thus I'm not the only one to view this the way I am so while I might not be adept at explaining this others appear to agree with me and unless you can provide a similiar outside source supporting your view I will say I see your opinion and raise you one opinion that agrees with me by one.
It might be of interest to speculate about the source of all the "expert opinions" which you have cited or to which you have alluded.
As far as I can tell, the earliest reference to dealing with TV load is found in installation instructions for the Eaz-lift WDH.
Eaz-lift Corporation was founded in 1952 when virtually all TTs were towed by the family sedan.
Current Eaz-lift WDH adjustment instructions (probably very similar to original instructions) state:
2 PROPER METHOD OF HOOKING UP WEIGHT DISTRIBUTING HITCH WITH HEAVY LOAD IN TOWING VEHICLE
A. Have proper size hitch to carry tongue weight of trailer and load in vehicle.
B. Measure towing vehicle before adding load to towing vehicle.
C. First measure distance between back bumper and ground and write it down.
D. Measure distance between front bumper and ground, write it down.
E. Add load to towing vehicle.
F. Hook up trailer to towing vehicle.
G. Raise front of trailer and back of towing vehicle above level with trailer tongue jack (approx. 3").
H. Secure spring bars to Hook-up Bracket.
I. Release trailer tongue jack.
J. Remeasure front and back of towing vehicle and have both settle the same amount or up to an inch lower in back by adjusting chain on spring bars.
K. You have now distributed the trailer tongue weight on both axles of the towing vehicle.
L. See step 7 on previous page.
Note that these instructions refer to "
HEAVY LOAD IN TOWING VEHICLE" as opposed to separate instructions which refer to "
LOAD IN TOWING VEHICLE".
Also note that the instructions refer to having both front and rear settle by the same amount ("equal squat") approach.
So, I'm guessing that current "expert opinions" all harken back to the early instructions from Eaz-lift.
Now -- let's recall the subject of "temporary cargo wt" which we were discussing.
You defined "temporary cargo wt" as weight which is added to the tow vehicle
AFTER the WDH has been adjusted.
I don't think any of the "expert opinions" pertain to cargo loaded after the WDH is adjusted.
IMO, our discussion deals with "apples" and your "experts" are dealing with outdated "oranges".
Ron