Harlock
Mojave, CA
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Joined: 05/10/2009
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If the trailer is heavy in comparison to the TV, you will be in for a bad day with crosswinds. My diesel mechanic always says you want to avoid towing anything that's heavier than the tow vehicle itself.
I almost lost everything when I was towing a 22ft TT with a Dodge Dakota. Came over a ridge on a severe wind day here in the desert and a sudden gust of wind sent it into severe oscillations. I let go of the throttle and just held on and eventually I got it back, but not without almost going into a ditch.
The next day I started shopping for a heavier TV. Bought a used F250 diesel and never looked back. Super easy and fun to tow now, and gets decent mileage for the setup. I have a stabilizing hitch but not a hensley. It has the bars that keep it stiff in side to side / roll movement. Works real well. Tried it without them once for a short tow across town and definitely noticed the difference.
Even in severe winds I don't notice it much anymore - the trailer can no longer pull the truck around - the truck weighs about 2,000lbs more!
2001 Aljo 225 Lite 22ft TT
2000 F250 Crew Cab 7.3L Diesel W/ECU Programmer
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Gman22
Burlington, Ontario
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Joined: 07/03/2008
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Rjlem wrote:Thanks for the all the info. I checked and my wheelbase is 128.3 inches. My towing capacity is 7,000. I have a Toyota Tundra with the towing package. According to those figures I figure 24-25 ft would be my limit. thanks again, Mel
You must be using the old the old 110" wheelbase for 20' of TT formula. That formula is a hang-around from back in the day when we use to tow with wood panel station wagons and without the advanced sway control systems available on the market today. It's why your Tundra manual says nothing of a TT length limitation rather it speaks to weight and the need for sway control.
Let that formula go, it's no longer relevant. Go by your weights, and invest in quality hitch hardware as required.
2009 KZ Spree 324BHS (LX)
2003 Ford Expedition 5.4L V8, 3.73
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Ductape
On the Road
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Joined: 11/15/2005
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Those old formulas are junk.
We've been towing a 24 footer for years with three different tow vehicles ranging from 106 - 112 inches, all over the states including western plains and the Rockies.
No sway problems; zip, zero, nada.
You need a properly set up quality hitch -We use an Equalizer brand- and a properly designed and loaded trailer and you won't have sway. We have a trailer with independent suspension and low COG.
I would rather tow this trailer with a short TV than a top heavy leaf sprung TT behind a long truck.
Our previous rig was a diesel truck and fifth wheel, BTW.
Surveyor SV-234
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npenn
Oregon
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Joined: 11/09/2007
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Ductape wrote:Those old formulas are junk.
We've been towing a 24 footer for years with three different tow vehicles ranging from 106 - 112 inches, all over the states including western plains and the Rockies.
No sway problems; zip, zero, nada.
You need a properly set up quality hitch -We use an Equalizer brand- and a properly designed and loaded trailer and you won't have sway. We have a trailer with independent suspension and low COG.
I would rather tow this trailer with a short TV than a top heavy leaf sprung TT behind a long truck.
Our previous rig was a diesel truck and fifth wheel, BTW.
Engineers use facts from calculations that are extremely accurate and do not rely on experiences and unfounded assumptions. Most calculations are conservative and allow for the many other variables as noted in this thread. Deviating from the calculations requires other factors to be in specifications or even better then specifications. Does not mean that one cannot as you pointed out deviate from the numbers and not achieve success. However, doing so raises the possibility of failure and the potential failure may occur under circumstances that have not presented themselves under your experiences.
That said, the formulas help make decisions especially when one is trying to vary more then a small deviation from the calculations. Lets say the TV can handle a 23 ft. TT but you are looking at 32 ft models that are in your GVW. I would suggest you consider a new TV or a smaller TT. However, if you are looking at a 25 ft TT with all other properties correctly configured then this deviation maybe acceptable.
I respectively disagree with your junk comment, the calculations are a very good reference point and should be considered.
Travel Safe
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Road Ruler
Canada
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Joined: 09/11/2003
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In many cases following the so called rules will put folks in dangerous or marginal towing situations. There is more to towing and towing safety than rules.
npenn wrote:
I respectively disagree with your junk comment
Perhaps a better way of saying it would have been " In many cases the old school rules may NA (not apply) which is the truth".
Airstreams.... the best towing trailers on the planet!
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Gman22
Burlington, Ontario
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Joined: 07/03/2008
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npenn wrote:Engineers use facts from calculations that are extremely accurate and do not rely on experiences and unfounded assumptions. Most calculations are conservative and allow for the many other variables as noted in this thread. Deviating from the calculations requires other factors to be in specifications or even better then specifications. Does not mean that one cannot as you pointed out deviate from the numbers and not achieve success. However, doing so raises the possibility of failure and the potential failure may occur under circumstances that have not presented themselves under your experiences.
That said, the formulas help make decisions especially when one is trying to vary more then a small deviation from the calculations. Lets say the TV can handle a 23 ft. TT but you are looking at 32 ft models that are in your GVW. I would suggest you consider a new TV or a smaller TT. However, if you are looking at a 25 ft TT with all other properties correctly configured then this deviation maybe acceptable.
I respectively disagree with your junk comment, the calculations are a very good reference point and should be considered.
Travel Safe
Engineers? How do you know it came from an engineer? Where did this formula come from.....honestly? It's been kicked around on the internet for years as if it's gospel. If there so much validity to it, why doesn't Ford mention it in my Expedition's manual? I'll bet you won't find it or any formula or trailer length limitation in any manual you check. Why??? Cuz to respectfully agree with Ductape.......it's junk leftover from yesteryear.
The question still stands - find me a reputable source to back this formula. Engineers at Ford speak to nothing in my manual other than weights and the need for sway control.
By this formula, a 3/4 ton F250 super cab with a 6.0 L diesel with a 142" wheelbase should tow no more than a 28' TT. If there were anything to this formula, all those 3/4 ton guys on this forum would be in big trouble.
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Ron Gratz
full time RVer
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Joined: 12/27/2003
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Gman22 wrote:---Where did this formula come from.....honestly? It's been kicked around on the internet for years as if it's gospel.
My thoughts on the subject can be found here. The following is an excerpt from that post:
IMO, we have no clear understanding as to how TT length affects TV/TT yaw stability. However, IMO, it is pretty clear that there are four primary factors which do affect stability. These are:
Tow Vehicle Weight
Tow Vehicle Wheelbase
Hitch Overhang (distance from TV rear axle to ball coupler)
TT Weight
The "guideline" attributed to RV.ORG ignores three of these four factors. My guess is that the "data" which were used to formulate the "guideline" might have contained some correleation between TV weight (which might be correlated to TV wheelbase) and TT weight (which might be correlated to TT length).
One could then take an "average" wheelbase for a range of TV weights and take an "average" length for a range of TT weights and come up with a wheelbase-length relationship for "safe" and "unsafe" TV/TT combinations. However, correlations that might have been appropriate for TV/TT combinations which existed in the 1950/60s (or whenever the unknown data were collected) might not be appropriate for combinations in use today.
Bluwtr49 suggested that the "guideline" is ultra-conservative. I agree. IMO, staying within all the TV manufacturer's weight ratings is the primary consideration. If you do that, then the TT length probably will be acceptable also.
Ron
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Road Ruler
Canada
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Joined: 09/11/2003
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Ron Gratz wrote:
IMO, we have no clear understanding as to how TT length affects TV/TT yaw stability. However, IMO, it is pretty clear that there are four primary factors which do affect stability. These are:
Tow Vehicle Weight
Tow Vehicle Wheelbase
Hitch Overhang (distance from TV rear axle to ball coupler)
TT Weight
Also include about another 45 factors. When optimally connected weight and a long wheelbase can be way down on the list.
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Ron Gratz
full time RVer
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Road Ruler wrote:Also include about another 45 factors. When optimally connected weight and a long wheelbase can be way down on the list.
I assume by, "way down the list", you are implying that weight and wheelbase are much less important than other factors.
Can you please list some factors which you consider to be much more important than TV and TT weight and explain why?
Ron
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shum02
Burlington ON CDA
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Joined: 04/22/2005
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Ron Gratz wrote:
Can you please list some factors which you consider to be much more important than TV and TT weight and explain why?
Ron
How much he spent on his hitch.
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