Weight math

[winojoe]

Just rented a trailer for my first adventure and would like to ask the community to check my math

Tow Vehicle:

Before adding trailer:

Front Axle: 2820 lbs
Rear Axle: 2800 lbs

After adding trailer:

Front Axle: 2640 (-160 lbs)
Rear Axle: 3880 (+ 1080 lbs)
Trailer Axle: 3000

Calculated trailer weight: 3900 lbs (Combined vehicle+trailer weight minus the vehicle weight before adding a trailer)_
Published trailer dry weight 3075 lbs.

I'm towing a 2020 Rockwood Geo Pro 19FBS.

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The dry weight is 3075 lbs and the published hitch weight is 413 lbs

I'm trying to estimate the actual tongue weight. If my math is right the tongue weight is 900 lbs, this sounds way out of line with the 10% rule-of-thumb number I've seen many times.

The trailer is lightly packed. All the tanks are empty. Has the accessories to hook up water and power, and the grey black water hoses. Has 2 full propane tanks (on the tongue) and two car-sized batteries on the tongue. Has kitchen supplies (all plastic and cheap). All storage bins are empty, fridge is empty.

Is it possible that by keeping the tanks empty I'm actually making matters worse? If the water tank is behind the trailer's axle then a full tank would reduce the tongue weight.

In any case, 900 lbs tongue is way beyond the rating of my vehicle, I might have to return the trailer.

Is my math wrong, something isn't making sense.

 

[TheLooks]

What is the tow vehicle and what is the payload?

 

[winojoe]

What is the tow vehicle and what is the payload?

There is no payload, The tow vehicle is literally empty other than a full tank of gas (it was full in both measurements above). There were no occupants in the vehicle at the time I weighed it.

 

[TheLooks]

That is what you are missing. What is your vehicle rated to haul? Not tow. You as a passenger are part of the payload.

 

[winojoe]

That is what you are missing. What is your vehicle rated to haul? Not tow. You as a passenger are part of the payload.

I'm not sure what difference that makes. it is rated to haul 5000 lbs with a 500 lbs tongue weight. Now that this is known, I still can't compute the actual tongue weight.

 

[TheLooks]

My Ram 3500 is not rated to haul 5000 lbs. What is your vehicle?

 

[TheLooks]

Do not confuse haul with tow....

 

[Rich W.]

Take it to the scales and you’ll know for sure. Vehicle on the scale, trailer off, and weigh the vehicle with the trailer connected and disconnected. That will tell you the actual (real) tongue weight.

 

[Kevin D Pem]

Yes!! You have calculated right!!! Why the trailer you rented has a 30% tongue weight is beyond me!!!
The weight is the weight with or without a driver. The information you gave is overkill, so this can lead to over analyzing things.

If I built a trailer that only had the proper tongue weight when loaded, I would get out of the business of building trailers. "Return it!!!".

 

[TheLooks]

Good lord Kevin, you went straight to the excessive tongue weight. But you have no idea what he is hitching it to. And he won't say. And he does not realize what payload and towing capacity are. I was trying to gently educate once I had enough info. I could care less what his front axle and rear axle are unless I know his wheelbase and ability to carry a load. But in the end the advice is correct, return the trailer or buy something that will tow it.