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lostagain
Senior Member
Joined: 06 Sep 2016
Location: Quaker Hill, CT
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Posts: 2595
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Topic: Have you weighed your 180? Posted: 28 May 2020 at 8:34am |
It would be easier to make a legal case against FR for the failure to provide a weight and balance sheet than to make one against them for someone who didn't follow the instructions using one. It's isn't that hard to write adequate disclaimers on a weight and balance sheet. A job for a first year law student.
Just like their use of a generic "owners manual" for most of their trailer lines, it's really a matter on not wanting to incur the cost of writing trailer specific materials.
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Never leave footprints behind.
Fred & Maria Kearney
Sonoma 167RB
Our Pod 172
2019 Ford F-150 4x4 2.7 EcoBoost
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offgrid
Senior Member
Joined: 23 Jul 2018
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Posts: 5290
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Posted: 28 May 2020 at 5:04am |
Yep, works in reverse Jato just like you're sayin'. One wrinkle though, the axle has to take any additional load not taken up by the tongue so when you add load aft of the axle, causing the tongue weight to go down, the axle load goes up faster than the load. The same is true of load in the back of the tow vehicle. In both cases adding load forward of the respective axles is almost always better.
Colt, I bet you can already answer your own question about FR providing a weight & balance sheet. Three little words; "avoidance of liability". You can't give someone a tool (W&B sheet, schematic, or hydraulic jack) and tell them to have at it, at least not without either assuring folks are trained in the proper use of the tool or have waived any claim to damages from improper use. It doesn't help them sell more trailers and it could cost them a bunch of legal fees, so why do it? Sigh...
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1994 Chinook Concourse
1995 RV6A Experimental Aircraft
2015 Rpod 179 - sold
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Colt
Senior Member
Joined: 16 Nov 2019
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Posts: 383
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Posted: 27 May 2020 at 9:55pm |
Yes. So you might want to shift some cargo forward to keep the C.G. forward of the axle.
Why doesn't Forrest River publish a weight and balance sheet to make calcs like this easier? Sure, I can build my own, but you know the engineers build one as part of the original design.
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John
'16 R-Pod 180
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jato
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Joined: 23 Feb 2012
Location: Kewadin, MI
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Posted: 27 May 2020 at 7:23pm |
Water weights 8.3 lbs per gallon so 30 gallons of fresh water weighs 250 lbs. Since the FWT is forward of the trailer axle, some of the additional load will go to the hitch and some to the axle. Measure the distance in inches from the trailer axle to the hitch and from the trailer axle to the midpoint of the FWT. The additional weight on the hitch will be 250 lbs times the distance from axle to tank divided by the distance from axle to hitch. The rest will go to the axle. If you only fill the tank half full then use 125 lbs rather than 250. Simple! [/QUOTE] OFFGRID
Would this work in reverse if figuring tongue weight on a 177 where the FWT is BEHIND the axle? So one would subtract tongue weight using the above formula?
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God's pod
'11 model 177
'17 Ford F-150 4WD 3.5 Ecoboost
Jim and Diane by beautiful Torch Lake
"...and you will know the Truth and the Truth will set you free."
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Colt
Senior Member
Joined: 16 Nov 2019
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Posted: 27 May 2020 at 7:13pm |
In fact I HAVE had to tow it with a full black tank. I could feel it. The level indicator was stuck and had no idea it was full.
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John
'16 R-Pod 180
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lostagain
Senior Member
Joined: 06 Sep 2016
Location: Quaker Hill, CT
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Posted: 27 May 2020 at 7:03pm |
I weighed my trailer at a public scale where I was able to get the axle weight, the tongue weight, TV rear axle weight, my fat butt, and the whole dang thing combined. Then I went home and compared the trailer axle weight and tongue weight using my Sherline scale. Getting the tongue weight is what they're for, so that was easy. I got the axle weight by jacking the trailer up on each side and gently lowering it down onto the Sherline. The combined axle measurements were surprisingly close to what I got at the scale. So, now if I'm going to be carrying a lot of different stuff than normal, I can get at least a ball park figure of what the trailer axle weight is as well as the tongue weight.
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Never leave footprints behind.
Fred & Maria Kearney
Sonoma 167RB
Our Pod 172
2019 Ford F-150 4x4 2.7 EcoBoost
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offgrid
Senior Member
Joined: 23 Jul 2018
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Posts: 5290
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Posted: 27 May 2020 at 5:53pm |
I think your weights sound good. 14% tongue weight is safe for sway and allows you some ability to add load behind the trailer axle (including gray and black water) if you wind up having to haul some waste water for awhile before you can dump. The only way the 442 lbs becomes an issue is if it is pushing your SUV's hitch capacity, or if it starts to push your SUV if you want to fill your fresh water tank for a boondock trip. If you want to find out what that would add on your tongue without having to do yet another weighing, here's a simple calculation:
Water weights 8.3 lbs per gallon so 30 gallons of fresh water weighs 250 lbs. Since the FWT is forward of the trailer axle, some of the additional load will go to the hitch and some to the axle. Measure the distance in inches from the trailer axle to the hitch and from the trailer axle to the midpoint of the FWT. The additional weight on the hitch will be 250 lbs times the distance from axle to tank divided by the distance from axle to hitch. The rest will go to the axle. If you only fill the tank half full then use 125 lbs rather than 250. Simple!
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1994 Chinook Concourse
1995 RV6A Experimental Aircraft
2015 Rpod 179 - sold
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Colt
Senior Member
Joined: 16 Nov 2019
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Posts: 383
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Posted: 27 May 2020 at 5:23pm |
Went and weighed the SUV. So, my 180 weighs 3122 pounds and the tongue weight is 442 pounds, ready to go and with a full water heater (50 lbs). So, it's about 100 pounds heavier than perfect.
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John
'16 R-Pod 180
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offgrid
Senior Member
Joined: 23 Jul 2018
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Posts: 5290
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Posted: 24 May 2020 at 6:39am |
The 2975 total seems low to me. If you got that by adding FR's tongue weight number than it is going to be low for sure. I think you need an actual tongue weight.
Here's how you can get it without having to disconnect the trailer back at the scales. Did you already get the whole rig weight when you were there? If not, go get that, then come home, drop the trailer, and go get the weight of the tow vehicle by itself. Then the trailer weight is
total rig - tow vehicle alone and tongue weight is total rig - trailer axle - tow vehicle alone.
If they'll let you, and they should because it only takes a few seconds, try to also get each axle's weight by adding an axle at a time as you go through the scale. You can then later use subtraction to get each axle weight. That will give you more data and improve the accuracy, but you can do it as I describe above and that should be good enough.
One more thing, if you have a WDH it needs to be in place but untensioned for the measurements. And leave it on the TV for that measurement.
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1994 Chinook Concourse
1995 RV6A Experimental Aircraft
2015 Rpod 179 - sold
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Gebaldwin1
Newbie
Joined: 14 May 2017
Location: CT
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Posts: 24
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Posted: 24 May 2020 at 5:52am |
Our's weighs in at average 2,950 lb. axle weight loaded (but no water). If you are weighing the pod while connected don't forget to add tongue weight to calculate full GVW.
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GMan
Lil' Bumpy - RPod 180
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