Tongue wt actual verus brochure way low

[Dave Pelletier]

Originally Posted by GP Bob

Well this is embarrassing. I just went out to check the tongue weight again with the Sherline and the first thing I noticed is that my stabilizers were still down. Sure enough, when I set the tongue on the scale this time it measured 675 lbs. That makes a lot more sense. Sorry for wasting your time.

Thanks for letting us know and I feel better knowing you have more than 350lbs tongue weight.

Cheers,
Dave

[Dave Pelletier]

Originally Posted by Old-Biscuit

Doesn't matter if Sherline in under trailer jack or trailer ball coupling as long as all the tongue weight is being carried by the Sherline Scale

actually it does (though I wasn't thinking and had it backwards in my previous post). you will get a higher weight reading at the jack vs. the ball. It's a class 2 lever arrangement:

https://xaktly.com/SimpleMachines.html

cheers,
Dave

[Tomahawk]

It does and it doesn't.
What I mean is it is close enough that it won't make much difference.
The actual tongue weight at the ball is the full weight of the trailer multiplied times the distance to the trailer CG from the center of the rear axles divided by the distance from the center of the rear axle to the ball. In my case the distance from the rear axles to the ball is 175 inch and from the ball to jack about 12 inches so you are either dividing by 163 or 175. If the tongue weight is about 10% then cg of the trailer is at about 17.5 inches. So the tongue weight measured at the ball would be WT*17.5/175= .100*WT, if you measured at the jack you'd get WT*17.5/163 = .107*WT. So measuring at the jack gives me about 7% error too high. Again in my case, that is about 45 LB of tongue weight. So when I measured 690 LB at the jack it was really about 650 LB.

[Old-Biscuit]

Originally Posted by Dave Pelletier

actually it does (though I wasn't thinking and had it backwards in my previous post). you will get a higher weight reading at the jack vs. the ball. It's a class 2 lever arrangement:

https://xaktly.com/SimpleMachines.html

cheers,
Dave

Not enough to upset the apple cart

If that close on weights then wrong truck/wrong trailer

[Dave Pelletier]

Agree with both of you; just wanted to point out that there is a difference - I never said it was huge or terribly significant only that you'll get different results if you measure at the jack vs. the ball.


Cheers,
Dave

[01tundra]

Originally Posted by Dave Pelletier

Oh, another thing; that Sherline scale goes under the jack right? If so the tongue weight would be more (not enough to make up the difference but still)

Dave

The Sherline scale I have is designed to go in the hitch coupler, same place as the hitch ball.

[Dave Pelletier]

Originally Posted by 01tundra

The Sherline scale I have is designed to go in the hitch coupler, same place as the hitch ball.

nice; I need to get one of those

Dave

[Tomahawk]

I didn't mention this in my previous response but to get the right tongue weight measurement you need to have the trailer level while measuring the tongue weight. On a dual axle trailer, nose down should make the TW go down and nose up will make it go up. This happens because the effect center of force (weight distribution on the tires) changes as the trailer is tilted. Tilt it far enough up and all the force will be on the rear axle because the front axle will lift off the ground. Similarly tilting nose down shifts weight to the front axle. The change center of force adjusts the lever arm ratios and hence the TW. Blah blah blah.

[Desert Flyer]

For normal levelness vs unlevelness, I doubt it would make much difference.

[GP Bob]

Originally Posted by 01tundra

The Sherline scale I have is designed to go in the hitch coupler, same place as the hitch ball.

That is also the way mine works. Unfortunately the first time I used it I thought I had raised the levelers enough. But no, they were still slightly touching the ground so my first reading was a shocking 350#. I was certainly glad to see the actual true tongue weight at 675#.

[allenb12]

That is where mine goes.

[ttavasc]

I have the 2000lb Sherline and the coupler extension unscrews so it can be used either under the jack or under the coupler. I thought they all did that but maybe not. For my purpose under the jack is close enough and is a lot easier than getting it on a stable platform high enough to go in the coupler. I had a spare small Pelican case sitting around empty so cut some foam and it makes for safe traveling. I happened to notice on the Sherline web site that they state to always store it upright so the case makes it easy to securely wedge it in the storage bay so it's upright.

[Tomahawk]

Originally Posted by Desert Flyer

For normal levelness vs unlevelness, I doubt it would make much difference.

You might be surprised.
Check out this video,

https://www.youtube.com/watch?v=XBZu39pQ8Gg&t=5s

.
In the video, the tongue weight changes by 110 lbs between the trailer on the truck with 5 psi in the air bags and the truck leveled with air bags. Those two cases illustrate the effect of leveling the trailer.

[01tundra]

I've always used wood blocks under the scale to get the trailer close to sitting
level, same way it sits when hooked to the truck.