Hi intheburbs,
Your right, I did not put calculations in for the passengers and fuel in the TV. I will add those to the next version that I do.
Your right, I did not put in calculations for the total weight on each of TV axles.
I assumed the total weight on the TT wheels was essentially the same as on the axles.
In the fall of last year after getting back from a trip to the east coast, I finally did decide to go weigh my rig on a cat scale. Wished that I had done that after I packed for the trip. The cat scale readings indicated that the trailer axle weight exceeded the 4400 lbs max axle rating by 120 lbs when connected to the suburban with WD active. The cat scale reading for the combined front and back axles of my suburban was under (7060 lbs) the max rating of 7200 lbs. The overload of 120 lbs on the TT wheels is what triggered my paranoia to work on a spreadsheet during the following winter months. I am retired so I had plenty of time to work on it. Maybe working on the spreadsheet slowed down the destruction of my brain cells with age. (smile :)) Since you mentioned the missing calculations for passengers and the fact that I know there was not passengers in the suburban when I had the rig weighed on the cat scales, I now believe the suburban may have exceeded its 7200 lbs max rating when both my wife and I were in it on the trip. I may need to not pack so much stuff in the 1500 suburban.
Also, on the trip to the east coast I was using an 800 lbs max rated WD hitch and I had to raise the hitch extremely high when loading the WD springs, which seemed odd to me while on the trip. When I got back from the trip, I started searching the web for what WD hitch manufactures recommended with my trailer tongue weight and the weight I had loaded behind the rear axle of the suburban, they recommended a 1200 lb unit. That probably explains why I had to lift the connected trailer hitch up so high to load the 800 lb springs. The spreadsheet I did also indicates that the 800 lb WD hitch I used on the trip was undersized. I now believe that when I adjusted the 800 lb WD hitch, I adjusted the tension on the springs to well over 800 lbs. I am lucky that the springs did not break on the trip. Talking about luck, originally the dealer I bought the trailer from installed a 600 lb WD hitch on my rig, I was totally new to travel trailering at the time and did not know better. Now I think the folk working at the dealership where I bought the travel trailer from did know much more than I did about WD hitches. My neighbor sold his travel trailer and kept his 800 lb WD hitch, which he then sold to me. I still was not smart enough to realize that an 800 lb WD was still to low of a unit for my rig. I am lucky that I did not break the 600 lb springs. It has taken me about 3 years to learn the hard way to know what I know now. I recently bought a 1400 lbs WD hitch to try.
Before I go on a trailering trip this year, I plan to weigh my rig on a cat scale again but this time I want to get the readings on the TT axles, the TV rear axle and the TV front axle.
Here is the URL for revision b of the spread sheet: http://thoughtsbydcg.files.wordpress.com/2014/03/travel-trailer-weight-calc7b.xls
Travel Trailer weight Calc7bI added the changes and additions that you mentioned to revision b.
David Geminden
