How to gauge your trailer's tongue weight on an ongoing basis

[bcp]

It would be interesting to see the results from towing with horizontal and vertical strain gauges in a trailer ball.

Bruce

 

[Kyle_in_Tex]

Simple, get your tape measure.

Measure the height of your trailer ball on your truck with nothing attached.

Stand on the ball and have someone measure it again with your +/- 200 lbs on it.

If it sags an inch or so, that is what you shoot for when loading your trailer.

 

[bcp]

Scale built into tongue jack:

Safety Jack, Tongue Weight 50080157 - Explosive Powersports

Bruce

 

[texasjohn]

Do you guys lay awake at night thinking about all this stuff? Or is it the nightmares?

I get a good nights sleep now BECAUSE I use a gooseneck for heavy loads and hauling cattle. In long years past, hauling with a bumper hitch, was always a white knuckle/nightmare event BECAUSE I understand the dynamic bumper hitch forces are NOT in your favor in emergency/dicey situations. And, those are the only ones that matter.

 

[JPRambo]

what about this method

 

[TomSeller]

Yup. Put a known weight on the tailgate and measure the drop. 200, 400, 600, 800 etc...

Yes. I just visually make sure my truck is squatting the way I like.

 

[newbury]

Have you ever tried this? It is surprisingly inaccurate.

That's what I did initially for measuring. With an accurate scale it's the same as just weighing the tongue IF you do the math correctly.

I have experimented with it, and it was not accurate at all. Could not repeat the measurements no matter how carefully I set up the apparatus. So I bought one of the commercial grade scales and my best measurements with the bathroom scale were off by almost 200 lbs.. A 30% error.

When I did it I changed one parameter from how they describe to do it on etrailer, I used a triangular fulcrum rather than a round one.

 

[aczlan]

If you have a hydraulic port-a-power you can do the same thing. I used a little 2" pancake cylinder. Gotta pump the cylinder up and hold it there in a vise or something (so it dont retract when the porta power is unhooked). So with it extended and full of oil, insert a pressure gauge.
A 2" cylinder has a surface area of 3.14 sq in. So every 3.14 pounds will register 1 PSI on the gauge.
Use a 0-100PSI gauge and you have a 314# scale
Or use a 0-10,000PSI gauge and you have a 31400# scale.
Or anything in between. If you have a different size cylinder, just do the math to get the ratio of PSIounds

You could also get a hydrualic rated tee and a pressure gauge, then put the tee/gauge just before the quick connect on the pump so you can always see how much pressure you are using.

Aaron Z

 

[schmism]

what about this method

yep it works fine

with this setup, i have my tractor loaded on it. I moved it around and marked it on the trailer and noted the various tongue weights. Then i hitched the truck up, and noted rear fender well squat dimension (measured with a tape measure) at the various points. Thus giving me a way to (mostly) recreate a known tongue weight on the back of the van based on any load on the trailer.

(FYI, as the springs are mostly linear (untill near the end of range), you see a fairly constant drop with increasing weight, so I can note how many lbs per inch of drop i have, so i can also get a reasonable "guess" at it even if the rear of the truck is loaded differently, as i can simply take a differential drop measurement)

Its not THAT much diffrent when i run my WD hitch as i have a range of rear wheel fender dimension i want to maintain and will adjust bar amount and or load shift to achieve the right "balance"

 

[Al Mac]

To get an approximate idea you could try this. Lets say you want 600# on the tongue. Park on a level surface and measure the bumper height. Next find a couple friends that weight a total of 600# and have them stand on the bumper. Measure the drop in height. Hitch the trailer and compare the drop to what you had before.

PS: asking the wife to stand on the bumper is not recommended!

Tom

A older gent ( I think he is passed) years ago hauled anything anywhere for $$$. He had a couple trailers and never knew what would be on them
next.
I was at a farm and he loaded a tractor with FEL and used a measuring tape. He just measured the height of his receiver when he parked and adjusted the tractor to the height he wanted for a good tongue weight.
Now he did this all the time so he knew what was a good height but I have used this idea some over the years and never had any problems.

Asking the wife would not work as she would never give you the proper number. :confused2:

Al