How Far Should The Ball Be From The Cab?

[Nessmuk]

Originally Posted by Jim-Bev-2363

Ray,

I do'nt know if you tried it or not but You Tube has lots of videos about fifth wheel towing. It is interesting to say the least.

http://www.youtube.com/results?searc...tallation&aq=f


I wonder if there are laws that you would be breaking by using such a small truck for this camper? In my mind, "if" towing fifth wheels with your Ranger is a good thing then why aren't there more people doing it? Wouldn't hitch manufacturers have specific models for your truck? There must be a reason information is so scarce.

Doh! Thanks, good idea.
There are fifth wheel and gooseneck set ups for Rangers and other small trucks still made, but most places only know about the heavy duty variety of parts because that is what most people use goosenecks and 5th wheels for.
I think that the lack of info comes more from the lack of small gooseneck and 5th wheel trailers. There are other companies that make them. or did, besides Sunline but there are very few and they made very few small GN or 5W trailers each year. I also think that with this trailer being so old, there is not enough info around on it. I think that may also be why more people are not doing it. It could also be the bed length on short bed trucks. Icould get a slide but paying $800 to $1000 to tow a $1500 trailer on a $3000 truck probably won't be worth it.

[Jim-Bev-2363]

A good excuse for a bigger truck.

[Nessmuk]

Checking on this:
Fifth Wheel Hitch Complete

[Nessmuk]

Originally Posted by Jim-Bev-2363

A good excuse for a bigger truck.

I am way too cheap for that!

[JohnB]

Originally Posted by Nessmuk

Where did you get the formula, if I may ask?

Does this formula work over a certain range? When I added my tag-along to my hitch, it added 220# or so to the rear of my truck, but did not change the front weight.

Hi Ray

To the 1st question the formula is known as calculating moments about a point. Where I got it was from my old text book, Statics and Strength of Materials by Irving Levinson printed in 1971. If you look at this post I showed Frank how I was doing this when he was working out how to figure weight and balance on his camper. Read down about 3 replies where I showed Frank this formula.

Homemade Travel Trailer Project

Does the formula work over a certain range? Yes it works over what ever length you can dream up providing the beam or truck bed does not collapse from the length. Like a 100 foot steel beam. If the beam cannot take the loads it will buckle and give way if it is not strong enough. There are no limits to length.

Originally Posted by Nessmuk

John, Thanks a lot for that great info.
I don't think this will work unless I can get a plate that moves the weight forward of the axle while putting the trailer behind it. I wonder if something cantilevered would work, or if I am looking for something called "magic".

I “think” I know what you are asking but there are some issues with what you are stating/wanting. If you want to bolt a plate says 3 inches forward of the axle and then extend back behind the axle say 6” unless the plate was never touching the truck bed except for the mounting point the weight will still apply in the truck bed where ever the pin load touches the truck bed. A plate will spread it out more even but it will not shift the load up to the bolting place unless you have some real heavy beam that will not flex under it’s load and not touch the truck bed.

If you get past that, this beam also comes with a lever effect trying to rip the plate out of it’s mounting location. A 600# pin weight hanging on a 12” long lever is 600 ft lb’s of static torque into the truck bed where it is bolted. Dynamic loads may be 3 times that or more. That is a fair amount for a sheet metal truck bed. While not impossible to do into the truck frame it needs to be heavy enough and thought thru.

The real issue is while you may have moved the loaded mounting point you now have a lever effect of the pin weight behind the axle still. The lever effect is going to still trying and will lift weight up off the front of the truck. You really did not move the problem.

If the camper is 7 foot (84”) and the cab to rear axle is 39. So if you ever wanted to do 90 degrees turn you need 42” to just scrape paint. However in a travel trailer I can only turn 74 degrees before I put the propane tanks into the truck bumper. I would love to turn 90 degrees but have not yet ever in all our TT camping as I can’t.

Maybe one of our 5th wheel towing folks can say how many time they turn 90 degrees. The issue is more magnified by how far behind the front of the camper the pin is. If the pin is forward of the front wall, you can turn more then if it is a few inches behind the front wall. Ideally take a tape measure place 0 on the ball coupler and then swing the tape measure in an arc and see where the width of your truck will hit the side of the camper. That angle would be the max you can turn.

I don’t know if any of this helps, but hopefully it plants some seeds of things to think thru

Hope this helps

John

PS You mentioned you have 220# on a tag along hitch and it diod not move weight off the front end. You mean towing on a ball in the truck bumper or receiver? If so, yes you removed weight off the front of the truck and added more then 220# to the real axle. If you can give me the rear axle overhang, distance from rear axle center to tow ball, I can tell you the axle changes. Use the same formulas. The weight moved, it just maybe you did not see a large change but the fenders heights did change

[Nessmuk]

John,
Thanks for all the input. Now that I think of it, after towing for a few thousand miles the outer edges of my tires were choppy. I remember thinking it was due to the reduced weight on the front end.

I did find out that Scamp, which still makes gooseneck trailers for small vehicles uses a hitch that bolts only to the bed, not the frame, of the tow vehicle. Talking to the parts manager, he said that they have had accidents where the trucks and trailers were damaged, but have never had a hitch tear out.
Their campers are 100# lighter on the pin and 500# lighter GTW. (That means I weigh 25% more, but is still only 500#) They also place the hitch directly over the axle in most cases, depending on the truck.
They deliver their gooseneck trailers all over the country on a 1998 Ranger 5 speed with that hitch in the same bed I have.
Their trailers are 4" narrower and curved in the front so that helps with turning.
I just thought people may be interested in what a company that is currently making these small trailers is doing. I'll keep posting what I find and would still appreciate any input that is offered.

[Nessmuk]

That tongue weight varied but was about 220# 46" behind the axle.

At one time I was at the full 8000# capacity of the truck with a full bed and trailer. It was not pleasant travel but the truck never complained. Probably due to the added cooling capacity.

[Nessmuk]

The hitch on this looks to be right about where I put mine.
http://www.sunlineclub.com/docs/83c.pdf

[JohnB]

Hi Nessmuck

I have never seen that brochure before. Interesting reading down memory lane.

However I did not see any reference to hitch mounting. Was there a page that you where referring to?

John

[Nessmuk]

John,
I was just referring to the pictures in the brochure. As it turned out unless I removed or replaced a cross member I had to mount the ball in front of the axle anyway. Even with the ball 1 3/4 to 1 7/8 in front of the axle it towed fine. I didn't hit the cab making full right angle turns. I may lower the nose a little, which will move the front of the trailer closer to the cab. We'll see how it goes. The nose is a little high right now, at least by sight.
I must say I liked towing the gn. No, or very little, sway when the 18 wheelers went by. It was even good in the strong winds we were having.

[JohnB]

WoW Great!! Any chance of some pics?

You have us really curious now

Good luck with your new coach!

[Nessmuk]

Thanks! And there will be pics. I think I saw the posting on how to post pics on the "Funline" thread. I owe Sunline Fan the # too.