how do I properly weigh my rig?

Lots of info here. I have used the CAT scales several times. Be sure to center the tow vehicle between the front and drive axle scales.

I am not sure what the tolerance is on the scale weight.

I want to thank Ron here for posting this procedure. Today I took my rig to a CAT scale and got the weights. Here are the results. If anyone sees any adjustments I should make, I'm all ears, but to my untrained and inexperienced self, these look like they should.

Weighing #1 (set up for travel)
front axle: 2540
rear axle: 2740
travel trailer axles: 3940

Weighing #2 (WD bars released but in place)
front axle 2300
rear axle 3040
travel trailer axles: 3860

Weighing #3 (Tow vehicle only)
front axle 2560
rear axle 2320


Tow vehicle weight: 4880

GCW: 9220
Trailer Weight: 4340
Tongue Weight: 460

Load transferred to TT axles: 80
Load transferred to TV front axle: 240

-Speak

hohenwald48 wrote:
I think I might be getting a little confused here. I don't see why you need to disconnect the trailer from the TV to get TW. Just relax the spring bars, subtract the weight of the TV unhitched from the weight of the TV hitched (with spring bars relaxed) and you get the true TW. Why to you need to weigh the TT unhitched if you already have the weight of the TV unhitched?

You don't need to weigh the TT unhitched.

If the scale operator will allow you to release the load from the WD bars while on the scales, you could make two separate weighings in one pass - one with WD activated and one with WD not activated.

If not, you would need to make three passes to get the full set of weights.

Ron

rbpru wrote:
But, the fact remains that I try to adjust the WD links so the TT is level with the TV or maybe a bit lower in the front; then weigh the combo to see what the max cargo and axel loads are.

rbpru wrote:
My best results have been to do what the TT dealer and Ford suggests. I put the TT on the ball, adjust the links so the TT sits level and the change in the height of the fenders at the wheels is about the same front and rear.

If you're talking about the front and rear fenders of your EcoBoost F-150, I believe you've misinterpreted Ford's specification for adjusting a weight distribution hitch.

The online 2011 F-150 Owners Guide specifies:

Weight-distributing hitch
When hooking-up a trailer using a weight-distributing hitch, always use the following procedure:
1. Park the vehicle (without the trailer) on a level surface.
2. Measure the height of the top of the front wheel opening on the fender, this is H1.
3. Attach the trailer to the vehicle without the weight distributing bars connected.
4. Measure the height of the top of the front wheel opening on the fender a second time, this is H2.
5. Install and adjust the tension in the weight distributing bars so that the height of the front fender is approximately halfway between H1 and H2.
6. Check that the trailer is level. If not level, adjust the ball height accordingly and repeat Steps 3–6.

Beginning in MY 2015, Ford changed Step 5 to read:

5. Install and adjust the tension in the weight-distributing bars so that the height of your vehicle's front wheel opening on the fender is approximately a quarter the way down from H2, toward H1.

(underline and bold added for emphasis}

Neither of Ford's specifications state that the change in the height of the fenders at the wheels should be about the same front and rear.
Both specifications require the front end to be above the unhitched height, and that means the rear end will be below the unhitched height.

If you're adjusting your WDH to cause nearly equal front and rear "squat", you're transferring significantly more load to the front axle than Ford calls for.
I don't know if Ford ever specified "equal squat", but I do know that since 2007 Ford has specified that the front end should be at or above the unhitched height.

Ron

I think I might be getting a little confused here. I don't see why you need to disconnect the trailer from the TV to get TW. Just relax the spring bars, subtract the weight of the TV unhitched from the weight of the TV hitched (with spring bars relaxed) and you get the true TW. Why to you need to weigh the TT unhitched if you already have the weight of the TV unhitched?

Plasticmaster

I depends on what you want to know.

If you are going to disconnect the TT and weigh it separately on the scales, with the axles on one scale and the hitch on another scale to find the true weight of the TT and its tongue weight, preferably when loaded, then you have to remove the hitch and bars for just the actual TT weight.

If you want to know the weight change on the TV when the TT is hitched up but not reduced by the spring bar tension, you need to weigh the rig with the spring bars resting on the back bumper. The hitch and bars are part of the tongue weight you are adding to the TV.

Normally the scales are used to determine what the load on the TV is with the TT hitched up and ready for the road; which is when compared to the weight of the truck by its self.

My WD hitch and bars weigh about 60 lbs. That is less than half a tank of gas.

Seems to me that without making 3 passes on the scales you will just be guesstimating the true tongue weight. If you're going thru the trouble of weighing your rig why not get all the information you can from the process? The whole idea of hitting the scales is to know the facts.

I think I would leave the spring bars just hanging in the sockets with the chains totally slack. Although they don't weigh a whole lot, they do weigh something and you might as well keep them in the mix. I would think they should be removed all together when weighing the TV only.

I plan on making 3 passes at the scale. When I weigh the entire rig WITHOUT load bars, do I just place the bars in the bed of my truck? When I weigh just the truck, do I keep the hitch and bars in the bed of the truck?

Not to belabor the point but the heaviest TV weight change measured on the scales was 13.3% of the TT weight, the lightest was 8.7%.

As far as towing stability goes there was no difference. I have a Blue Ox hitch with stabilizers designed in.

Maybe the 25 ft length is more forgiving.

rbpru wrote:
I agree but the tongue weight while towing is what matters.

Let's say a 6000 lb loaded trailer has 800 lbs of tongue weight.---

Okay, that's a TW% of 13.3%.

How did you determine that the TW is 800#?

Ron