Tongue weight IS ABSOLUTELY a factor of cargo or payload weight. If, for example, payload weight is 1200 lbs., and the tongue weight of a 5000 lb trailer is 500 lbs (10%), then 500 lbs must be subtracted from the payload weight. Your payload is now 700 lbs. Generally tongue weight should be roughly 10 to 15 percent of the loaded trailer’s total weight – no more, no less. You want more payload, then tow a lighter trailer and reduce the tongue weight. You want max payload, then leave the trailer home.
Let me try to explain this differently. You're mixing up different things, I think. I've been told that the Ascent has a GCWR (gross combined weight rating) of 11,000 pounds. That's towing and vehicle and cargo in vehicle. That's 5,000 pounds towing, plus a total of 6,000 pounds of vehicle and in vehicle.
BTW, I suspect that tongue weight is factored into *gross axle
weight* and not GVWR. You'll find that if you add up the gross axle weights, you're over 6,000 pounds, btw.
Now, how do I know that tongue weight remains the same? I don't for sure. But, I am currently crossing my fingers and going by what two Subaru Product Specialists and one Subaru Product Manager assured me, which is that with the Ascent "fully loaded" (6,000 pound total vehicle and in vehicle cargo & passengers) can *still*
tow 5,000 pounds. By law (federal regulations), the tongue weight must
be 10% (or more) of the towing weight for a Class III hitch and vehicle combo. That means that if Subaru is insisting it will tow 5,000 pounds, then the tongue weight must be 500 pounds. They are claiming it will still
tow 5,000 pounds while fully loaded, and by doing so, are implying (because it's the law) it will still have a tongue weight of 500 pounds.
- The 2018 Pathfinder is similar. GCWR is GVWR plus tow (5,000 pounds) for a total of 11,000 pounds
- Another vehicle mentioned earlier has a GCWR of 8,600 pounds, which means interior cargo definitely does reduce its tow weight, and, when tow weight is reduced, so is tongue weight.
I think the confusion comes in where there are other vehicles where the *tow* weight is a factor of how much cargo/people are in the vehicle. You will notice that the GCWR for such vehicles is not
the tow weight plus the GVWR. In that case, you'd be almost
correct. To be 100% technical, the tongue weight is NOT
being reduced by the inside cargo weight. The law doesn't allow it to be measured that way. The *tow*
weight is being reduced by the inside cargo weight, and the tongue weight, being a factor of tow weight
, is being reduced accordingly (10% tow weight). Tongue weight calculation is very simple. It uses tow weight.
IF you're horrendously bored, you can start with CFR, Title 49, Subtitle B, Chapter III, Subchapter B, Part 393, Subpart F, §393.70 and read through it all, and follow it to the other parts of the regulations.
ALL OF THAT SAID:
Keep in mind that none of us has yet to see the official GCWR. It's not on any of the door plates I've photographed, nor any that others have, and I have not yet been able to get a hold of the vehicle manual (it was not yet available as of the last time I checked). It is entirely possible that the GCWR is not 11,000 pounds.
The Subaru team might have been wrong - but they were correct on everything else they told me, including there being both 4 pin and 7 pin trailer harness connectors (everyone else, including numerous dealerships were saying only a 4 pin). So far, they're batting 1,000. Hoping they got this one right as well.
So, who knows? If the GCWR is 9,000 pounds, that changes things considerably. If it's what the Subaru Brand Specialists say, we're all set, and the tow weight is 5,000 and the tongue weight is 500 - and inside cargo/passengers won't change that.