Reply
 
Thread Tools Search this Thread Display Modes
 
Old 08-21-2014, 09:50 PM   #15
Rivet Master
 
A W Warn's Avatar
 
2000 25' Safari
1999 34' Excella
Davidson County, NC , Highlands County, FL
Join Date: Aug 2006
Posts: 2,568
Quote:
Originally Posted by Ron Gratz View Post
The values for "trailer tongue weight" presented cells F71, F73, and F85 are based on the value in cell F67 which is calculated as (G45+I45)-(G49+I49).

Ron
Error corrected.
Thanks Ron

Towing weight calculator and result analyzer-rev1.xls
__________________

__________________
Alan
2014 Silverado 1500 Crew Cab 5.3L maximum trailering package (yes, I'm towing the 34')
A W Warn is offline   Reply With Quote
Old 08-21-2014, 11:26 PM   #16
Rivet Master
 
2016 30' Classic
Erie , Colorado
Join Date: Oct 2013
Posts: 1,245
Images: 1
And a big thanks to Ron as I believe that my spreadsheet and many other calculations are based on his original post. Really does help dial in a WD system.
__________________

__________________
Gary
2015 Classic
2015 GMC Sierra 2500HD Duramax
ProPride
NVPN
ghaynes755 is offline   Reply With Quote
Old 08-29-2014, 07:24 PM   #17
Rivet Master
 
A W Warn's Avatar
 
2000 25' Safari
1999 34' Excella
Davidson County, NC , Highlands County, FL
Join Date: Aug 2006
Posts: 2,568
Quote:
Originally Posted by ghaynes755 View Post
And a big thanks to Ron as I believe that my spreadsheet and many other calculations are based on his original post. Really does help dial in a WD system.
Gary,

I got back from a week of camping this evening, so I am just now reading your post. I found a spreadsheet you posted in another thread. Is this the one you are referring to? (http://www.airforums.com/forums/f464...ml#post1460987). I wanted to see if I could learn something from your spreadsheet. I found it works specifically for your truck, but not for everyone without some modification.

I was trying to create a spreadsheet that anyone could use, even someone that knows nothing about Excel formulas/spreadsheets, a spreadsheet that anyone can read the instructions, simply fill in the blanks, get the result, without doing the math/calculations. I want the spreadsheet to work for any tow vehicle, for any hitch, for any sway control, and for any trailer.
__________________
Alan
2014 Silverado 1500 Crew Cab 5.3L maximum trailering package (yes, I'm towing the 34')
A W Warn is offline   Reply With Quote
Old 09-12-2014, 11:11 PM   #18
Rivet Master
 
A W Warn's Avatar
 
2000 25' Safari
1999 34' Excella
Davidson County, NC , Highlands County, FL
Join Date: Aug 2006
Posts: 2,568
Tow Vehicle Weight Ratings

I'm a little disappointed that there have been so few comments on the calculator spreadsheet! Two weeks and no one has tried it?
I was hoping to get some feed back, good or bad.

I'll move on to another subject: Tow Vehicle Weight Ratings.

Generally, a tow vehicle will not carry its maximum payload while towing its maximum trailer load without exceeding some other limit. I created a chart to demonstrate this so that I would know how I could load my truck and trailer.

The chart shows the load limits of my tow vehicle and the varying loads upon it as payload and trailer weights change.

The chart highlights the three different trailers that I tow, at their GVRW.

The chart demonstrates the point at which payload has to be decreased as a heavier trailer is towed.

Hope you find this helpful.
varying towing loads.pdf

add edit:
After I posted I noticed some of the color coding is incorrect. Too late to do over and re-attach it. The numbers are correct.
__________________
Alan
2014 Silverado 1500 Crew Cab 5.3L maximum trailering package (yes, I'm towing the 34')
A W Warn is offline   Reply With Quote
Old 09-14-2014, 02:02 PM   #19
4 Rivet Member
 
Livingston , Texas
Join Date: Dec 2007
Posts: 394
Quote:
Originally Posted by A W Warn View Post
The chart shows the load limits of my tow vehicle and the varying loads upon it as payload and trailer weights change.
Alan, your chart is a novel approach at demonstrating the relationship between trailer weight and available payload for given values of GCWR and TV Curb Weight.
Expressed as an equation, that relationship is:
Available Payload = GCWR - TV Curb Weight - TT GVW

Your chart also shows the relationship among TT weight, tongue weight percentage, and tongue weight for six values of TW% from 10% to 15%.
And, via color coding, the chart shows those combinations of TT weight and TW% which produce tongue weight in excess on a given value (1200#).

Although not stated, the "Available Payload" must include the vertical load which the TT imposes on the TV.
I think it would be informative to show how much payload capacity remains after accounting for the vertical loading.
I also think the tongue weight values currently displayed in the right six columns are not a particularly good use of space since they are easily calculated by a simple multiplication of TT weight times TW%.

I would recommend that, instead of tongue weight, you use the right six columns to display "Remaining Payload" which would be defined as your current "Available Payload" minus vertical load imposed by the TT. The vertical load could be set equal to tongue weight, or it could be some percentage of tongue weight to account for the effect of WDH load transfer to the TT's axles.

For example: using the 9800# weight of your Excella and assuming vertical imposed load is equal to tongue weight, you could calculate and display "Remaining Payload" values, instead of tongue weights, for the six TW%s.
At 9800# the six values of "Remaining Payload" would be 620, 522, 424, 326, 228, and 130# for TW%s of 10, 11, 12, 13, 14, and 15%.
The relationship is:
Remaining Payload = TV GVWR - Curb Weight - Vertical Imposed Load

In addition to displaying the Remaining Payload values in the six right columns, you also could use color coding to indicate those combinations for which the calculated tongue weight exceeds a given value.

Now, I expect that you and I will be scolded for obsessing too much about weight and ratings -- but, hey, it's your thread.

Ron
__________________
Ron Gratz is offline   Reply With Quote
Old 09-14-2014, 04:24 PM   #20
Rivet Master
 
A W Warn's Avatar
 
2000 25' Safari
1999 34' Excella
Davidson County, NC , Highlands County, FL
Join Date: Aug 2006
Posts: 2,568
Ron,

As always, I appreciate your thoughts. Thank you!

My original purpose was not to evaluate the results of one specific weighing or one specific tow vehicle, but to evaluate a varying range of weights and different vehicles.

I created this spreadsheet last year when I was considering purchasing my next tow vehicle (obsessing may be correct). I was trying to understand the possibilities of different vehicles. At the time I did these evaluations it served its purpose. This spreadsheet helped me understand which tow vehicle would work for me. The document you see is the results of one of those evaluations, the one with my truck specifications plugged in.

The purpose for the multiple columns showing the varying hitch load percentages: To demonstrate how shifting cargo within the trailer allows one to tow a heavy trailer while staying within that 10%-15% load range, and specifically for me to understand when shifting of cargo would be necessary with each vehicle being evaluated. It would also show me when it would be beneficial to remove cargo from the tow vehicle and relocate it into the trailer. Also the columns demonstrate the point the hitch load would exceed the manufacturer's hitch load limits. They also demonstrate the load points where weight distribution is required due to varying load.

What you see is just a portion of that spreadsheet. I printed it as a pdf document to share it, hoping it would be used as a tool to help someone understand that even if a vehicle is rated for a maximum load, it will not tow that load and carry the maximum payload at the same time.
__________________
Alan
2014 Silverado 1500 Crew Cab 5.3L maximum trailering package (yes, I'm towing the 34')
A W Warn is offline   Reply With Quote
Old 09-14-2014, 04:37 PM   #21
Rivet Master
 
A W Warn's Avatar
 
2000 25' Safari
1999 34' Excella
Davidson County, NC , Highlands County, FL
Join Date: Aug 2006
Posts: 2,568
Quote:
Originally Posted by Ron Gratz View Post
Now, I expect that you and I will be scolded for obsessing too much about weight and ratings -- but, hey, it's your thread.

Ron
I hope so!
Anything is better than being ignored!
__________________
Alan
2014 Silverado 1500 Crew Cab 5.3L maximum trailering package (yes, I'm towing the 34')
A W Warn is offline   Reply With Quote
Old 09-12-2015, 11:37 AM   #22
Rivet Master
 
KYAirstream's Avatar
 
1979 31' Sovereign
Northeastern , Kentucky
Join Date: Feb 2011
Posts: 622
Just came across this post last night and wanted to say thanks, A W Warn, for putting that spreadsheet together in post #15 above. I hope you don't mind a few questions...

As far as the data input, what did you put for the Propride? 100lbs on the tongue and 100lbs on the TV?

Also, how did you determine the "Spring Bar Actual Weight" ?

Did you just estimate the contents of the cargo for "Payload inside TV behind axle" ??

The center column under "Your Hitch" also asks for ball mount and ball weights. Where do those four entries come from?

I also liked your tow vehicle weight sheet in Post #18. Do you happen to have that in an excel file?

Sorry for all the questions. This seems like a great tool and I just want to make sure I get it right.
__________________
KYAirstream is offline   Reply With Quote
Old 09-16-2015, 06:11 PM   #23
Rivet Master
 
A W Warn's Avatar
 
2000 25' Safari
1999 34' Excella
Davidson County, NC , Highlands County, FL
Join Date: Aug 2006
Posts: 2,568
Sorry it took so long to get back. I've been in the mountains in NH without cell service or internet.

I'll answer as best I can from memory.

Enter the entire weight of the PP where there is a blank for it in the spread sheet. Do not try to adjust any portion to tongue weight or payload.

Weigh the spring bars on a scale. This is not the bar rating, it is the weight of the material. There is also a blank for the rating at another location.

I actually weighed everything I might carry. I keep a list so I can add the items so that I can estimate the total before going to a scale. (If I remember correctly, the payload is a calculation based on filling in blanks. It is extremely important to follow the instructions)

(from memory) One place there is a blank to enter the actual weight of the materials (ball & mount). I weighed mine on a bathroom scale.

Then there is a place to enter the load rating of each, stated in pounds. The rating is stamped on each piece.

The Excel file I have is only for my truck, specifically. Unless your truck is a 2014 Silverado 1500 with the max trailering package, it will not work for your truck.
__________________
Alan
2014 Silverado 1500 Crew Cab 5.3L maximum trailering package (yes, I'm towing the 34')
A W Warn is offline   Reply With Quote
Old 09-16-2015, 06:29 PM   #24
Rivet Master
 
KYAirstream's Avatar
 
1979 31' Sovereign
Northeastern , Kentucky
Join Date: Feb 2011
Posts: 622
Thanks for the reply. Hope you had a great trip to the mountains.

I'm using a propride, so I assume just disregard the weights for ball and mount, since the propride weight is entered elsewhere?

Anyone know how much 1,000lb bars weigh?
__________________
KYAirstream is offline   Reply With Quote
Old 09-20-2015, 05:53 PM   #25
2 Rivet Member
 
NHAir's Avatar
 
Currently Looking...
Atkinson , New Hampshire
Join Date: Sep 2015
Posts: 35
Alan, thank you for initiating this thread. I hope you enjoyed your trip to New Hampshire!

As a new member to the Airstream Forums, I am beginning to discover the data rich repository which is available to the members.

I happened to be reading the 2016 Flying Cloud Owner’s Manual which I downloaded from the Airstream website. Since I tend to be wicked anal about safety, I turned to section seven which talks about towing and loading your trailer. I was glad to see a discussion on pages 7-3 and 7-4 which goes into detail regarding the use of public scales to weigh your trailer and arrive at three weights which are specific to your trailer and contents.

1. Trailer’s total weight, cannot exceed GVWR (Gross Vehicle Weight Rating).
2. Trailer’s weight on axles cannot exceed GAWR (Gross Axle Weight Rating)
3. Weight on trailer tongue

I then searched the Forum threads and discovered your work.

(It is important to remember I am an Airstream (FC 25 FB Twin) wannabe. I will also be new to RVing. I am an ocean kayak expedition guy who understands the importance of weight distribution and how important it is to safe control of the vehicle. I go to great efforts to weight and distribute my gear in the hatches of my kayak. It would make sense to me the importance of performing the same tasks in a travel trailer.)

Alan, do you think this approach is reality for most campers? I suspect if you are careful concerning your weight limits and distribution, you experience improved towing performance and handling of your travel trailer. Is that true for you?

Warren Parlee
__________________
NHAir is offline   Reply With Quote
Old 09-21-2015, 09:42 PM   #26
Rivet Master
 
A W Warn's Avatar
 
2000 25' Safari
1999 34' Excella
Davidson County, NC , Highlands County, FL
Join Date: Aug 2006
Posts: 2,568
Quote:
Originally Posted by NHAir View Post
snip...........
Alan, do you think this approach is reality for most campers? I suspect if you are careful concerning your weight limits and distribution, you experience improved towing performance and handling of your travel trailer. Is that true for you?

Warren Parlee
I can't answer for most campers. But - I think many people do not understand how the balance of load in the trailer affects the handling characteristics of the tow vehicle, so they unintentionally create problems.

Also, many people use a larger than necessary tow vehicle and therefore compensate for out of balance loads in the trailer.

When I tow my 25' trailer with my 1/2 ton pickup, I do not have to be as concerned about loading. Since I have been to the scales many times to check, I know from experience what I can and cannot load.

When I tow my 34' trailer I have to pay special attention to loading the trailer and the 1/2 ton truck. Anal? You might say that! I MUST keep the tongue weight to ~10% of the trailer's gross weight. I also must remove any unnecessary cargo from the truck and place it inside the trailer. If the trailer tongue is any heavier than ~10%, the GVRW of the tow vehicle will be exceeded. I am more likely to weigh the vehicles each time when towing the larger trailer. (at least until I get more experience with this trailer)
__________________

__________________
Alan
2014 Silverado 1500 Crew Cab 5.3L maximum trailering package (yes, I'm towing the 34')
A W Warn is offline   Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Why do new trailers weigh more? tlsmit1 Towing, Tow Vehicles & Hitches 24 08-08-2013 05:08 AM
30/34' slide out tongue weigh question bluegrass Hitches, Couplers & Balls 4 08-02-2010 03:42 PM
Tongue weight and weight distribution Bex Hitches, Couplers & Balls 8 06-06-2010 01:11 PM
Total Weight & Tongue weight of 24' Argosy woody_strohm Our Community 3 12-21-2008 11:25 PM
Tongue weight verses tongue height - level the WD hitch? HowieE Hitches, Couplers & Balls 12 11-17-2007 02:02 PM


Virginia Campgrounds

Reviews provided by




Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 12:10 AM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.

Airstream is a registered trademark of Airstream Inc. All rights reserved. Airstream trademark used under license to Social Knowledge LLC.