Best Practices for Accurately Weighing a Converted Trailer

[VegasBell]

I made an effort to calculate the dry weight of my converted 12X6 single axle trailer. Went to the local truck stop and paid $15 to get on their scale. Of-course that weight included truck, trailer and myself. When I say dry weight, I mean that includes everything I carry in the trailer except food, water and clothes. So here’s my calculations. BTW, I tow with a 2018 Tacoma 4x4 SR5 Access Cab, and I have a fiberglass camper shell.

Weight of truck and trailer 7360 lbs
Curb weight of truck -4425
Fiberglass shell -200
Truck contents -75
10 gal gas -80
driver (me) -200

Net trailer weight = 2380
Trailer dry weight new -1335
My conversion added appx. 1045 lbs

I'm guessing that I'll add about 300 lbs of food, water and clothes for a trip. That means that I’ll only be about 300 lbs short of the trailer’s GVWR of 2990lbs. Which is about what I was expecting, but more than I had hoped. What do you think? Is that a solid method for calculating weight? Thanks!

Fred

 

[Pmullen503]

It would be more accurate if you had actually weighed the truck without the trailer on the same scale at the same time.

 

[KCStudly]

The CAT scale near-ish to me has multiple plattens so the trucks can weigh individual axle sets. When I weighed my loaded UT I pulled on to the scales with the hitch straddling the parting line of two of the plattens and uncoupled before getting the weight. That way I ended up with separate TV and trailer weights with minimal maneuvering.

 

[outintheforest]

In Oregon we keep the scales on, even when the shift is over. It's easy to weigh everything in as much detail as you want. I'm curious to see what my tongue weight will be.

 

[bullchuck1]

Next time ask for an axle weight on the truck and trailer. Add the two axles of the truck together and subtrac that from your total weight of everything, then you will have the weight of your trailer. This way you don't have to unhook the trailer This is from an old truck driver.

 

[KCStudly]

... except the tongue weight will be more biased on the TV, not fully accounted for in the trailer weight.

 

[WYWander]

I'd also recommend using the truck scale and disconnect the trailer. It doesn't have to be difficult though. You don't need to move anything after disconnecting.

Pull your rig so your tow vehicle is on a single deck and the trailer wheels are on the next deck behind, but also so the tongue jack is above that same rear trailer deck. Put the jack down and lift it just enough to get it off the hitch, then ask them to weigh. Connect, go in and pay, then go back around and park in the same exact spot, but don't disconnect and ask for a reweigh. A reweigh will be cheaper. First weigh is $15, a reweigh is $5. Whatever moves between the decks in the reweigh should be your tongue weight.

Considering the low weight of the whole thing, the accuracy should be within less than 10 lbs.

 

[cwegga]

If it is a CAT scale you can reweigh for not very much money for a while after your time across the scale for full price. Don't unhook on the scale and block it for others, just weigh twice. Once with everything hooked up, then pull off into the parking where there is space, unhook and go back through to weigh just the truck. Then subtract the truck from the total weight. That allows you to get the actual not calculated trailer weight and also figure out tongue weight by doing some math.

 

[DrewsBrews]

@cwegga method is what I did. This seems to be standard practice for the CAT scale I went to. The scale operators acknowledge such small trailers are not heavy enough to get an accurate number by themselvs (mine was under 1000lbs). They are meant to weight trucks up to 80,000lb and such a small weight barely even registers. Often teardrops and small trailers are lighter than the TV, so using the TV as "base weight" brings the zero point up farther into to the scale's accuracy range. You also want all tires to be on only one section of the scales (if it will fit) because of the same reason. I believe each section is a seperate scale.

Here in Ohio we must have an acceptably accurate trailer weight measurement to register a self built trailer (weighed at a scale approved by Department of Weights and Measures). They risk their license being revoked if caught providing inaccurate data. So I trust their methods provide the most accurate results possible from their scales. If I were to try any other method, I'd bet they would refuse to sign off on the registration documentation as an official measure.

Tongue weight is not needed here for registration.. More for personal information. I got tongue weight by placing a bathroom scale under the tongue jack when on level stable ground (I added a 2x6 chunk between to protect the scale from the jack foot) and gently lifted the coupler off the ball with the jack. The closer the jack is to the coupler the more accurate it will be. Might be prudent to try first with the trailer unloaded to verify it won't overload the scale, and watch the scale as you unload the weight off the ball.