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Old 06-26-2013, 11:29 AM   #1
Rainer
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Figuring Weights - Please Check My Logic

Upon leaving for this first journey I went to a public scale and proceeded to get the following weights (all in pounds):

a) GCWR - the truck and trailer together - 21,540
b) the trailer on the scale but the truck off - 10,420
c) the truck alone on the scale - 8,660

from these I deduced the following:

weight of the trailer = a - c = 12,880
pin weight = b - c = 1,760

According to the brochure the trailer weighs 9,731 empty and can carry 2,389 for a total trailer weight of 12,120. This seems to indicate that I'm 760 pounds too heavy.

Will those in the know check my math and let me know if I'm correct in my computations.

On a side note, I did fill the water tank full just to get these maximum weights.
 
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Old 06-26-2013, 12:42 PM   #2
8.1al
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I'm confused too. b+c should equal a
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Old 06-26-2013, 01:28 PM   #3
Rainer
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Remember that B is weight of the trailer on the scale but STILL connected to the truck, so the truck still supports part of the weight of the trailer even though it isn't on the scale. That difference, according to my calculations, should be the pin weight.
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Old 06-26-2013, 02:48 PM   #4
8.1al
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OK, those numbers check. Let's forget the brochure for a minute and what does the sticker on the side of your trailer say for GCWR?
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Old 06-26-2013, 03:02 PM   #5
Irlpguy
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Rainer something is not adding up. If the truck was disconnected from the trailer and is 8660 then at that point there is no pin weight on the truck. The trailer axles weighed 10,420 and together they weighed 21,540.

If you add the trailer axle weight (b) to the truck alone (c) you get 19,080. Subtract that from the total of 21,540 and you are left with 2460. That should be your pin weight.

This of course assumes the truck was not hooked to the trailer when weighed. If it was then your numbers just don't add up.

If the truck when weighed was not connected to the trailer then this is what you would have: (below)

Add the truck weight alone 8660 to the 2460 pin weight and you have a Truck GVWR of 11,120

When you now add the GVWR of the Truck (11,120) + Trailer axle weight of (10,240) you now get your GCWR or the total of both on the scale of 21,540.

You can add the pin weight to the trailer axle weight and get your trailer GVWR of 12,880

Hows that for adding. All looks correct to me.
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Old 06-26-2013, 03:06 PM   #6
Countryfolks
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"A" - "B" is the total not on the scale, so (A-B)-C = Pin weight. The pin weight + trailer weight = gross trailer weight.
21540-10420=11120 not on the scale: 11120-8860=2260, pin weight: 2260+10420=12680: 12680-12120=560
I think that's right, if not, someone will be along and get me straight.
This is assuming the truck was not disconnected which is the way I did it.
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Old 06-26-2013, 03:11 PM   #7
Irlpguy
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With the fresh water tank full you have added somewhere between 500 and 600 lbs to the total weight.
Check you GVWR on the sticker on the trailer and the GVWR of the truck on the drivers side door. You will know where you are at then as far as how close you are to capacity, over or under.

Good to see someone doing all you have done, and getting an understanding of it as well...
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Old 06-26-2013, 03:38 PM   #8
Irlpguy
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Countryfolks your math was a little out, the pin weight you calculated is out 200 lbs, likely a slip on the calculator.

This is the information you will find on your Trailer sticker:

GVWR - Maximum the trailer should weight when both pin weight and axle weight are combined.
GAWR - Gross weight rating of each axle. (ie: 7000# Axles are rated at 6750#)
Cargo Carrying Capacity - includes full fresh water tank, and empty waste water tanks.
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Old 06-26-2013, 04:03 PM   #9
richfaa
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I have always wanted to say this..... It will pull it fine....
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Old 06-26-2013, 04:30 PM   #10
kab449
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Next time you weigh pull on the scale slow and take the front axle reading (a), then the front axle and rear axle together as they sit on the scale (b), then the gcwr of the rig (c). Then disconnect the trailer and weigh the truck only taking note of the front axle only (d), and both axles on the truck (e).

Pin Weight=B-E
Rear Axle Weight Loaded=B-A
Trailer Weight= (C-B)+Calculated pin weight.

Make sure your not over your RAWR and FAWR per the sticker on your truck
Make sure you don't exceed your GTWR listed on the trailer plate.


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Old 06-26-2013, 06:15 PM   #11
pineranch
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What number are concerned about?
1. GCWR
2. Pin weight
3. Truck front/rear axle weights
We tend to get into the weeds on this topic.
Mike
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Old 06-26-2013, 07:14 PM   #12
Recumbent
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I have never weighed, but know I should do so, the best part of weight threads is Bingo's weight police cartoon?
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Old 06-26-2013, 07:47 PM   #13
Irlpguy
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There are two things you can look up easily:
1) GVWR of your truck (drivers side door panel)

2) GVWR of your trailer (sticker on the trailer somewhere)

Steps to finding what else you need/want to know.

A) Load your truck with everything you will be likely to carry when heading out, also full of fuel and passengers, now weigh the truck alone. Weigh each axle individually so you will know later how much weight from the pin goes on the front/rear axles.(information only) The total of the axle weights = the total weight of truck.

B) Load your trailer with everything you will likely carry in it and haul it to the scale, while hooked up, weigh truck front axle, then weigh truck rear axle, finally weigh the trailer axle.

When you subtract the two truck axle weights obtained in (A) from the two truck axle weights obtained in (B) you will have your pin weight. You can compare the front/rear axle weights to know how much weight was added to each axle (information only).

Now if you add the now known pin weight to the axle weight of the trailer obtained in (B) you will have the total weight of the trailer.

Hooked up weights of truck front axle + truck rear axle + trailer axle = the total combined weight of the two vehicles.

Don't worry about front/rear GAWR of the truck as together they will exceed the GVWR of the truck anyway.

Now that you know how much your truck weighs including the pin weight you can compare that to it's GVWR.

Now that you know how much the trailer weighs pin+axle you can compare that to it's GVWR.

That is it, and all you really need to know. Are you over or under the listed capacities.

Knowing the "actual" weight (pin + axle) of the trailer is important, you can now calculate how much weight your tires are carrying and what tires will give you a safety margin and how much. All good stuff easily obtained by following the above steps first.
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Old 06-27-2013, 01:45 AM   #14
Ozz
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Good one Rich
Where can I see Bingo's weight Police cartoon ?
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Old 06-27-2013, 02:12 AM   #15
bncinwv
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Wow, Rich has reformed his ways and is actually displaying a sense of humor?? Never thought I would see the day. Guess I will have to clue the WP (Weight Police) in on this thread and send them to the rescue since the request was made!!

They are watching you:



Other than that, I have nothing to contribute to this thread due to my self-imposed, long-standing promise that I would never post my thoughts on a weight-related thread. (For instance: Nothing about engineered Safety Factors or the sort, or the fact that to this date, I have yet to weigh anything other than my self occasionally to see if the winter weight-gain has went away!! ) Now that I have provided such deep, thought-provoking comments, I will slink away back to my sideline position in anticipation of a great upcoming Fourth of July!! Have Fun!!

Bingo
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Bingo and Cathy - Our adventures begin in the hills of WV. We are blessed by our 2014 3850FL Big Sky (previous 2011 3750FL and 2007 3400RL) that we pull with a 2007 Chevy Silverado Classic DRW CC dually.
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Old 06-27-2013, 05:26 AM   #16
Irlpguy
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The OP took the time to go and have his unit weighed and posted that information here with the request the math be checked for accuracy. Amazing to see what happens after that.

Several folks responded and no one suggested he might be overweight or otherwise, so no Police work going on there.

Then along comes an escapee from the “funny farm” who just had to make a joke. This of course leads to more escapees joining in wanting to see the “weight police” joke. They don’t weigh their vehicles and have nothing constructive to add but post short and long responses anyway. Not sure who you are mocking with reference to the weight police, would that be everyone who responded.

My humble suggestion: 1) Have the administrators post a sticky with the “weight police” joke so it is there in perpetuity so those that want to, can get their jollies without disrupting a thread on weight.
2) If you have nothing constructive to add, “sit on your hands”.
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Old 06-27-2013, 05:43 AM   #17
8.1al
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Yes, he is overweight. We're not talking about him pulling more that his truck is rated for, it's his trailer. I don't know what size tires he has but there is a good chance they are overweight. A carrying capacity of 2500 lbs. of so may seem like a lot but it's difficult to keep from overloading. That's why we looked for one with 3600 lb. carrying capacity. He did say that he had a full tank of water so if he only traveled with a small amount that would help a lot.
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Old 06-27-2013, 06:28 AM   #18
bncinwv
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Quote:
quote:Originally posted by Irlpguy

The OP took the time to go and have his unit weighed and posted that information here with the request the math be checked for accuracy. Amazing to see what happens after that.

Several folks responded and no one suggested he might be overweight or otherwise, so no Police work going on there.

Then along comes an escapee from the �funny farm� who just had to make a joke. This of course leads to more escapees joining in wanting to see the �weight police� joke. They don�t weigh their vehicles and have nothing constructive to add but post short and long responses anyway. Not sure who you are mocking with reference to the weight police, would that be everyone who responded.

My humble suggestion: 1) Have the administrators post a sticky with the �weight police� joke so it is there in perpetuity so those that want to, can get their jollies without disrupting a thread on weight.
2) If you have nothing constructive to add, �sit on your hands�.
You have provided validation as to why weight-based inquiries on this forum are a no-win proposal. Long-time members have seen many discussions regarding this, and these discussions always end up the same. The majority of the combinations are indeed overweight due to the nature of the size of the rigs and the capacities of the TV's. Then it morphs into a legal discussion regarding liabilities and many disagreements as to the legal responsibilities of those who are construed to be overweight. A sticky or a link on the home page would indeed be appropriate to provide the proper calculation methods and formulas to be available for members to make an educated, informed decision based on their analysis. Sorry for the digression from the OP's question, but judging by the information provided by some, one should always remember, that just because it is on the internet, does not mean that it is true. There have been many threads regarding proper methodologies for weighing the truck and rig and ascertaining the relevant weights. What one does with that knowledge is up to that individual. Keep in mind that levity here and there can be a good thing!! As always, I am not offering advice or input, one way or the other, because I have learned from experience!

Bingo
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Old 06-27-2013, 07:07 AM   #19
Irlpguy
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Bingo, I think there are a good number of folks that want to know what the weight of their trucks and trailers are. I provided a list of steps to determine all those weights by taking your vehicles to a weigh scale. My suggested method may be no better or worse than anyone else, however it is an easy way of determining some accurate numbers. If one chooses not to know what the weight of their particular unit is, that is up to them.

I make no judgement on whether Rainer is overweight or not, I only tried to confirm his math. Being overweight and knowing it, is up to the individual not me.

This thread had not morphed away from the OP, until certain posts were made. They added nothing to the topic, and I believe were intended to distract. That my friend is not levity, that is downright ignorant.

I am now sorry I posted at all and apologize to the OP for this and any other off topic posts, unfortunately I have also allowed myself to be taken off topic.

I guess I am being taught a lesson by some "Long-Time" members.
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Old 06-27-2013, 07:25 AM   #20
bncinwv
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Ed and Rainer,
There is no need to ever apologize for posting questions and/or answers that contribute to knowledge and education as well as reflect personal opinions. There is always valuable information available if one has the wherewithal to pick it out and put it to use. There is occasionally some mumbo-jumbo voodoo as well, after all, it is an internet-based forum. Just because a thread digresses and detours along several paths does not mean it is any less a valuable thread. And I will maintain that sometimes the off-topic posts are sometimes very entertaining. I hope and believe that Rainer got his questions answered, because the information is there and presented well (by Irlpguy and others). As I stated, I made a personal vow to myself to never post on weight-based threads, and unfortunately I broke my own vow since a picture was requested. Look on the bright side, at least we have not had any excessively flaming retorts! Been there, had those. The other thing to always keep in mind is that it is difficult to decipher emotions and intents from posted words (this is why I always use emoticons, so hopefully, the forum members know when I am being a little sarcastic or humorous (which happens a lot!). Once again, I will slink back to the sideline!!
Bingo
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