Re: [SilverStreak] size of propane tanks

["Tom Patterson" <pattersontj@xxxxxxxxxxxxx>]

Sadly, you can find contradictory postings as to hitch weight elsewhere, 
even on the Sherline site.  Whatever, I think that this posting originally 
dealt with the necessity of maintaining sufficient tongue weight to avoid 
sway.  That still is the main point.  Too much weight can damage the tow 
vehicle, which is the other item  to avoid.

I don't tow a tricycle, but rather a tandem axle trailer, and I don't 
experience sway, nor do I have anywhere near the weight which would damage 
my tow vehicle.  I am very happy with 800 lbs. tongue weight from a 4,500 - 
5,000 trailer which follows the tow vehicle obediently during an average 
useage of around 10,000 miles per year.  In my case, I have an excellent 
tongue weight situation.

The original posting did not address the type of tow vehicle to be used, but 
this may well affect the tongue weight desired by that member.  In any 
event, suggestions have now been provided for weights from between 7% and 
20%.  If practical, I suggest he try for about 15%.

-Tom

----- Original Message ----- 

> Minimum 15% sounds more like a 5th wheel/gooseneck trailer. They are 
> commonly up to 25% of the total trailer weight for towing by pickup trucks 
> or flatbeds. (Freight semitrailers are typically 50%-50% 5th wheel-trailer 
> axles.)
> The recommendations (such as SS owner's manual) for weight on the trailer 
> tongue (at the coupler socket where it goes on the hitch ball) BEFORE 
> tensioning the spring bars is usually 10%-15%. One says 7%-12% but that's 
> the only one I've seen.
>
> TYPE OF TRAILER               PERCENT OF WT. ON TONGUE
> Single Axle                   10% minimum/15% maximum
> Tandem Axle                   9% to 15%
> Travel Trailer                11% to 12%
> 5th Wheel                     15% to 25%
> Reference: www.sherline.com/lmbook.htm#refrn9
>
> Conventional travel semitrailers are tricycles. The single "virtual" front 
> wheel of the trailer is at the center of the rear axle of the tow vehicle. 
> A hitch ball provides no roll resistance to the trailer. All roll 
> stability is provided by the trailer axles. A weight carrying setup (no 
> WD) becomes less and less resistant to trailer roll as the proportion of 
> the trailer weight is shifted to the hitch. A WD hitch shifts part of the 
> tongue/hitch load to the trailer axles - "weight transfer" - increasing 
> trailer roll stability toward its maximum, which is if there was no load 
> on the hitch and all trailer weight was on its axles. Such would likely 
> sway like mad at the slightest provocation, but it wouldn't roll. WD 
> hitches are never supposed to be set up that tightly.
> 5th wheel hitches that rock freely from side to side for several degrees 
> give no roll stability from the tow vehicle until the 5th wheel rocks to 
> its limit. Some have hydraulic dampers to provide some roll stability to 
> the trailer from the tow vehicle.
> Gooseneck/stinger (farm/utility trailer) hitches (ball in the truck bed) 
> give no roll stability other than the friction of the coupler socket on 
> the ball, which if greased should be very slight. They depend entirely on 
> the trailer axles for roll stability. The lower the center of gravity, the 
> less roll tendency.
> Illustration of roll: www.sherline.com/lmbook.htm#refrn9 under
> "Driving In Windy Conditions"
> Illustration of sway (tailwagging of either or both trailer and tow 
> vehicle): www.sherline.com/lmbook.htm#refrn9 under "More Towing Tips"
>
> "NOTE ABOUT LOAD EQUALIZING HITCHES...
> "A load equalizing [weight distributing] hitch is selected base[d] on the 
> trailer's actual tongue weight rather than on gross weight. This type of 
> hitch has some real advantages, but government studies have shown they can 
> actually work too well, lightening the load on the rear wheels of the tow 
> vehicle sufficient to reduce traction. This kind of hitch should be 
> selected carefully, installed by professionals and its operation 
> understood by the user." www.sherline.com/lmbook.htm#refrn9 scroll between 
> 1/2 and 2/3 down the web page
>
> The spring bars should be rated such that the loaded trailer weight is 
> between the spring bar spec limits. Too light for the trailer weight and 
> the spring bars can't be tightened enough to do a good job. Too strong and 
> the spring bars may do nothing (go loose) on road crests and practically 
> lift the tow vehicle rear axle off the road in dips. The load on the tow 
> vehicle rear axle should never be less than the tow vehicle rear axle load 
> without the trailer.
>
> Keneth, the weight sticker on the door post or edge should give the 
> maximum load for the axles individually. The tires are often the limiting 
> factor. Neither rear (or any) tire should ever be loaded beyond its 
> maximum load rating printed on the sidewall. If you have duals, note that 
> the dual load rating is less per tire than for single loading.
> The Dual Cam sway control is a separate device from the WD system. The 
> spring bar cams used to be added on to the spring bars, and still can be 
> obtained for adding to straight spring bars. Newer Cequent (Draw-Tite, 
> Reese, Fulton, Wesbar, Bulldog, Crown Eclipse, Hidden Hitch, Bargman, ROLA 
> and Tekonsha are the Cequent brands; not all are used on hitches) spring 
> bars come with the spring bar cams formed into their rear ends so no 
> separate spring bar cam is needed. The parts for each system, old and new 
> models, are different but the function is the same.
> The Dual Cam system functions by locking the tow vehicle and trailer in a 
> straight line. This has enough "give" to allow rounding gentle curves 
> without unlocking the cams. For sharp turns the cams release (with a 
> "bonk" or "graunch" sound, which disconcerts new users!) and allow nearly 
> free swiveling until the combination returns to a straight line, then the 
> cams lock again.
> The Dual Cam instructions prohibit greasing the cams. They should be kept 
> clean; only a very light grease of the vaseline kind is permitted if the 
> creaking sound of rounding gentle curves is too annoying.
>
> You probably already know these things - some who read these posts may 
> not.
> Al