Shank length on draw bar --longer or shorter?

[redbarron55]

Originally Posted by Carol H

...
As far as getting the right height goes the only sure way of doing that is to again load up the trailer and attach it to the car. Once you have towed it you may need to fine tune it and find yourself the proud owner of more than one draw bar. ;-) ....

Originally Posted by gordon2

How true.. I have three draw bars. If I had it to do over again, I would buy one adjustable. But now I might need sway control, so I might be buying more stuff anyway. Such is the life of a trailer owner.

Perhaps you need a set of air shocks or bags?
Do you readjust your headlights each time you have a different loading or don't drive at night?
If a car is equipped with HID lights for example and it is from the factory it must have either self levelers or shutters or automatic headlight correcting systems.
A little more weight on the rear springs really calls for a little higher spring rate to keep the resonant frequency of the system higher and keep it further from the danger zone.

[Roger C H]

Changing the factory suspension may void your vehicle's warranty. Contact your dealership or the manufacturer before making any modification to your vehicle.

Lowering the suspension should be done with a sway bar replacement to prevent body stress, which can ultimately damage your vehicle.

Read more : http://www.ehow.com/how_6027255_choose-right-suspension-car.html

Our owner's manual says not to use weight distribution systems.

[Carol H]

Originally Posted by redbarron55

Quote:
Originally Posted by Carol H View Post
...
As far as getting the right height goes the only sure way of doing that is to again load up the trailer and attach it to the car. Once you have towed it you may need to fine tune it and find yourself the proud owner of more than one draw bar. ;-) ....

Perhaps you need a set of air shocks or bags?
Do you readjust your headlights each time you have a different loading or don't drive at night?
If a car is equipped with HID lights for example and it is from the factory it must have either self levelers or shutters or automatic headlight correcting systems.
A little more weight on the rear springs really calls for a little higher spring rate to keep the resonant frequency of the system higher and keep it further from the danger zone.

Nope there is nothing for airbags to fix. The vehicle is not dropping in the rear with headlights point to the sky as it has beefed up shocks & I am pulling a trailer well under half its towing spec. As I said every vehicle is different and some vehicles just like more weight on the tongue than another might in order to achieve a solid tow

There is an easy fix to the problem of using sway control on multiple receivers - Reese Sway Control Bracket for 3" Ball Mounts - Class III & IV.

You can use it & move it easily to any receiver/ball mount that you already own. No need to have a plate and ball welded to each one for the sway control.

[EllPea in CA]

Originally Posted by redbarron55

If you check the unloaded height of the rear and compare to the laden height this will usually cause the camber to increase and perhaps the toe out as well.
This is not an issue with a solid rear axle, but with the IRS it could be.
The suspension is designed to work within a range of ride height and if it is lower tire wear could be accelerated and also not handle as well.
The Airbags simply put the suspension in the proper area.
Again research indicates that the use of airbags to level the TV provides 1/2 of the benefit of having a weight distribution hitch. Mostly by putting the rear end at the proper level. This provides more advantageous roll coupling front and rear and with the trailer. The leveling of the TV with the WD is a large part of the reason for it's use.
The other is the transfer of weight off the rear to the front wheels and the trailer wheels. A lot of stress accompanies this weight shift as well. This is of course why many manufacturers discourage the use of WD hitches.
If you want 1/2 of the benefit of the WD hitch, and a level car so that the headlights are the same towing or not, keep the rear tires from wearing, and improve the handling for about $100.00 then try it.
If it doesn't match your idea of the proper universe then (of course) don't add them. They do not add load capacity to the car, just add enough spring rate to bring the car back to level with the additional load.
The reason I brought it up is if you measure the ball height of the trailer hitch and set the ball on the car at that level then you merely add air to keep it there when loaded.
Lots of benefit and little cost.

Thanks JD, I'll have the hubby read this post.

[Joe Romas]

Originally Posted by redbarron55

Again research indicates that the use of airbags to level the TV provides 1/2 of the benefit of having a weight distribution hitch. Mostly by putting the rear end at the proper level.

If air bags provide only 1/2 the benefit of a WDH why would a person choose air bags over a WDH?

[MC1]

Originally Posted by Joe Romas

If air bags provide only 1/2 the benefit of a WDH why would a person choose air bags over a WDH?

That is a good question.

My thoughts....

The bags are cheaper and once installed you are done, unless you need to add or decrease air pressure. By comparison the bags tend to make for a rougher ride.

With a WDH more work and effort is required to install every time one hooks up or unhooks.

I agree, generally speaking the WDH is the way to go. Added stability and safety.

[redbarron55]

The above and also they help with other loading issues as well.
The suggestion from the studies in the '70's is to use the two in combination.
The air bags took up all that they could and the hitch did the rest.
Part of the equation has to do with the spring rate of the rear eand suspension and the applied weight. When you add weight you lower the resonant frequency of the system. If the period of any oscillation (from incipient sway for example) is the same as the period of the spring system then the system will be unstable.

As an aside to Ellpea - Volvo has the shock in the middle of the springs and air bags will not fit. There are no air shocks to fit that I can find, but Volvo has some Hydraulic self levelers (very expensive) that may work. here is a picture of one:



It would seem that the only acceptable solution for many is a nice truck with a weight distributing hitch and all that entails.

Ride height is important and spring rate as well. The Volvo seems to have a pretty beefy rear suspension and I wouldn't worry about it. If you have many miles on the car you might consider freshening up the suspension. If the shocks would fit from other models then these migh be an option. There are cheaper places to buy the springs and shocks together. here is a video:

[PC Steve]

Originally Posted by Joe Romas

If air bags provide only 1/2 the benefit of a WDH why would a person choose air bags over a WDH?

If that is all the weight transfer needed, that's why. It is a cheaper, simpler, lighter solution. You don't always need the biggest hammer...

Neither solution is inherently bad.

[honda03842]

I'm also a believer in getting the load as close to the rear axle. I believe in tow vehicles with short distances from ball to rear axle and moving the ball as close to the axle as possible.

Look at the picture of Harvey's ball for example in post 3. You could pull the pin on Harvey's ball and shove the ball's shaft further into the receiver by maybe 2 inches. Mark the spot and have a new hole drilled.

This picks up a few percentage of improvement for virtually no cost.

Small thing but in the correct direction.

One year the Lakers had the best basketball team but did not win the championship. The next year the coach's position was to get every one to improve by 1%, small stuff possible for every one, small stuff that makes champions.

Also I don't believe in the use of pins with spring clips in critical positions. I have seen a spring clip fail. Also evil hands can create a disaster. We use a key locking pin in this critical position.

[Joe Romas]

Originally Posted by honda03842

[snip]

Also I don't believe in the use of pins with spring clips in critical positions.
[snip]
Also evil hands can create a disaster. We use a key locking pin in this critical position.

X2, My hot water heater door with a metal latch suspiciously aome open after stopping at a rest stop with a bunch of 18 wheeler's

I also put screws in my 2 plastic refrigerator covers for that reason

[Bob Miller]

Considering the vey low tongue weight allowable, and the small FGRV Ellpea will be towing, IMHO, all this talk of adding air bags, changing spring rates or considering a self leveling system is, pure and simple, a lot of Hooey.


I have towed three different 13' FGRV's substantial distances, with three different vehicles, two of which had very low towing capacities, and never needed to even consider suspension modifications. It's almost like saying that putting 150 lb. sack of sand in your trunk, or two extra adults in the back seat, is going to have a drastic effect on handling. Just isn't so.


And I see that the fears of the "resonant frequency", and the results of towing with now 40+ y.o. vehicle designs, are again rearing their ugly heads.

[Jon in AZ]

Originally Posted by PC Steve

If that is all the weight transfer needed, that's why. It is a cheaper, simpler, lighter solution. You don't always need the biggest hammer...

Do air bags actually transfer weight? Seems to me all they do is stiffen the rear suspension to maintain a level ride, which is all that's needed if the tongue weight is within the manufacturer's hitch weight and rear axle capacities. But perhaps I'm misunderstanding how they work...

[redbarron55]

"ONLY" 1/2 the value if a WE hitch. Actually that is quite a lot.
Also a part of the benefit of the WE hitch is the added friction of the bars and force on the ball etc.
Just a little info for anyone who is curious and would like a little more information.
All advice worth price charged.


Sent from my SCH-I605 using Fiberglass RV mobile app

[redbarron55]

The WE above is part of the Samsung auto correct.
Another thought or wonderation is if the added stress from the WD hitch contributes to the cracking of three frames on these light trailers?
A contributing factor is the built in flex from the cut down doorway adding stress to the other side.
Not as visible is the cracking on the top of the tube that passes under the doorway. This is hard to see without having the floor out.
At least as much force has to be transferred to the trailer frame as the TV frame.
This would mean that the weight on the trailer tires is higer, especially when the pair are traversing a dip in the path.
These trailers have pretty light weight tubing forming the frame.
The Scamp was originally 14 gauge and later they moved up to 12 gauge or about 1/8 inch.
I used 12 gauge on my rebuild for this reason and my right side under door tube was split where it attached to the front tongue.
The left side was broken and poorly repaired at the bend as well.


Sent from my SCH-I605 using Fiberglass RV mobile app

[Jack L]

I have air bags on my Tacoma 4X4 and they are handy for hauling heavier loads without the trailer too. They can be used to level the truck when hauling a load when the load is heavier on one side of the bed.

[redbarron55]

Originally Posted by Bob Miller

Considering the vey low tongue weight allowable, and the small FGRV Ellpea will be towing, IMHO, all this talk of adding air bags, changing spring rates or considering a self leveling system is, pure and simple, a lot of Hooey.


I have towed three different 13' FGRV's substantial distances, with three different vehicles, two of which had very low towing capacities, and never needed to even consider suspension modifications. It's almost like saying that putting 150 lb. sack of sand in your trunk, or two extra adults in the back seat, is going to have a drastic effect on handling. Just isn't so.


And I see that the fears of the "resonant frequency", and the results of towing with now 40+ y.o. vehicle designs, are again rearing their ugly heads.

Not quite the same since the 300 or so pounds is not in the trunk or in the rear seats, but rather is 6 inches or so behind the rear bumper.
Kind of like that generator on the rear bumper of a trailer with the weight too far back.
The key is the g force it takes to shift the handling from understeer to oversteer. The additional stiffness in the rear helps to keep this under control.
Also the roll coupling is affected especially with the ride height lower and more if the rear end is a solid axle where the roll center is at ground level.
But this gets more complicated and it is beyond me explaining.
I used to fool around with a few race cars and back then we towed them with pickups and cars.
No matter what I try to explain will irritate someone, so I think I will just let it go.
By the way before I go the air bags don't appreciably shift any weight, but they do correct the geometry and set the caster and camber correctly on the front since the car is level. If the rear is IRS then the geometry would be improves for ti as well.
Basically if you are not towing with a nice truck and a WD hitch you are doing it wrong, Why bother with a small light trailer in the first place if this is the case?
As Bob said with the light trailer it is most probably not an issue.
tow more and worry less. especially since the Volvo has no air bags available!

[Bob Miller]

Quote: "Basically if you are not towing with a nice truck and a WD hitch you are doing it wrong, Why bother with a small light trailer in the first place if this is the case?"


Care to explain that to the vast majority of us on this site why we are all doing it wrong?

[Carol H]

Originally Posted by redbarron55

Basically if you are not towing with a nice truck and a WD hitch you are doing it wrong,

sure hope this is being said tongue in cheek.

If not I would suggest perhaps a test tow with something other than a truck might be in order.

Don't get me wrong I like my truck but I would not hesitate to suggest that there are a number of alternative vehicles that can and will provide a fair more stable and enjoyable tow of a 13' or 16' fiberglass trailer under all weather conditions without the need for a WD or airbags to keep it all together.

[EllPea in CA]

I'd be happy to not only tow more, but to tow at ALL! Our receiver and drawbar are all sorted, but the struggle with the plugs continues. I appreciate Bob Miller's help today; he even called the trailer service for me to help explain what needed to be done!

Anxiety is beginning to ensue. Will this rig be ready by Friday? I'm no longer certain.