New Tow vehicle- need WDH?

[gypsydad]

Originally Posted by Bobbo

OP, please note that this is absolute rubbish. You may or may not need a WD hitch, but EVERYBODY needs sway control. Any trailer can sway under the right conditions, and sway is dangerous. Sway can make your tow vehicle unstable, or even roll it over. That is also not to mention the possibility of a swaying trailer hitting a car in the next lane over.


OP, please note that this is absolute rubbish. No WD hitch makes it difficult to go around a curve. If there is a problem going around a curve, it is because you are driving too fast. The WD hitch has zero to do with that.

Agree, 100%. Easy for someone to say "you don't need a WDH or Sway Control"; it's not their "investment"! Like Clint said in a famous movie; "do you feel lucky"?

[jcl]

Originally Posted by Bobbo

OP, please note that this is absolute rubbish. No WD hitch makes it difficult to go around a curve. If there is a problem going around a curve, it is because you are driving too fast. The WD hitch has zero to do with that.

I agree with you, but to clarify what Andy453's comments refer to, I would modify your statement to say that no WD hitch, properly set up, makes it difficult to go around a curve.

Andy453 has previously referenced a 1970's study whereby WD was applied excessively, with far more than the recommended bar tension, to the point that the rear wheels of the tow vehicle were not in full contact with the ground. Yes, steering around a curve can be difficult in that condition. The obvious response is, don't do this. It is classified as user error.

Andy453 has a RAM pickup. RAM anticipated some owners being confused about this subject, and so they clearly recommend WD for both their light duty and HD pickups, and they included the attached drawing in their owners manuals to help people made better decisions. See the bottom graphic. Yes, that configuration could be difficult to steer around a curve. But the second graphic, with less than recommended WD, and the front axle consequentially unloaded, can also be difficult to steer around a curve. The best handling combination, and the safest combination, is with WD applied appropriately.

[Andy543]

It seems that no matter how simple an explanation you give, there will always be someone there to deny it. This is particularly true when discussing weight distribution/sway control hitches. So, let me propose a simple test, the results of which can be clearly seen in real life.

Consider the skid-pad test. This is a test that the automotive world uses to measure the ability of a vehicle to go around a turn. A circle is drawn on the pavement, typically around 300' in diameter, and the vehicle tries to drive around it, with slowly increasing speed, until it can no longer hold onto the circle or, in the case of a vehicle towing a trailer, until it jackknifes. At this point the speed is noted and the lateral g-force is calculated. The g-force can then be compared to other vehicles or other configurations. You can go to Car and Driver, who regularly performs this roadholding test and reports the results in their specifications for many of the vehicles they test. Typically, a pick-up truck will fail at around 0.7g's.

Now, put a trailer on that truck and perform the test again. See what the maximum g-force is. Then add a weight distribution/sway control hitch and perform a third test.

This should be a standard test for anyone who wants to be in the trailer hitch manufacturing business. I'm not saying the hitch manufacturer should be required to pass this test, but they should be required to provide test results for their hitch on request. Then everyone will be able to see what they are buying.

Unfortunately, hitch suppliers have been spreading false information for years, mostly through fear mongering, in order to sell their products to an unsuspecting public. This is particularly egregious when a hitch is sold to a person with an undersized tow vehicle. The customer leaves the dealer with an accident waiting to happen.

[jcl]

Originally Posted by Andy543

It seems that no matter how simple an explanation you give, there will always be someone there to deny it. This is particularly true when discussing weight distribution/sway control hitches. So, let me propose a simple test, the results of which can be clearly seen in real life.

Consider the skid-pad test. This is a test that the automotive world uses to measure the ability of a vehicle to go around a turn. A circle is drawn on the pavement, typically around 300' in diameter, and the vehicle tries to drive around it, with slowly increasing speed, until it can no longer hold onto the circle or, in the case of a vehicle towing a trailer, until it jackknifes. At this point the speed is noted and the lateral g-force is calculated. The g-force can then be compared to other vehicles or other configurations. You can go to Car and Driver, who regularly performs this roadholding test and reports the results in their specifications for many of the vehicles they test. Typically, a pick-up truck will fail at around 0.7g's.

Now, put a trailer on that truck and perform the test again. See what the maximum g-force is. Then add a weight distribution/sway control hitch and perform a third test.

This should be a standard test for anyone who wants to be in the trailer hitch manufacturing business. I'm not saying the hitch manufacturer should be required to pass this test, but they should be required to provide test results for their hitch on request. Then everyone will be able to see what they are buying.

Unfortunately, hitch suppliers have been spreading false information for years, mostly through fear mongering, in order to sell their products to an unsuspecting public. This is particularly egregious when a hitch is sold to a person with an undersized tow vehicle. The customer leaves the dealer with an accident waiting to happen.

The first rule of holes, is that when you are in one, you should stop digging.

You continue to talk about WD hitches without acknowledging the importance of how the combination is set up. It makes no sense to publish test results for skid pad tests without paying attention to the combination setup. The tow vehicle, the WD hitch, the trailer, are all less important than how the combination is set up.

In your example, most solo vehicles will understeer on a skid pad. It is intentional on the part of the vehicle designers, as they want to protect consumers from themselves. Some of us purchase vehicles that are far closer to neutral in handling, by design. Others don't care.

You then claim that when you hitch up a trailer, with WD, it will oversteer (bold emphasis, above) You use the term jackknife, but we are talking about oversteer. A jackknife is different, it can happen at slow speed in reverse for example, when people back up a trailer. But on a skid pad, with a WD hitch and a trailer, the combination will understeer if you set it up like the second graphic (insufficient WD), even more so than solo operation, and it will oversteer if you set it up like the third graphic (excessive WD). It doesn't matter what the make of the hitch is, these outcomes are generally true. It is more complicated than this, as things like WD head tilt angle and tire pressures will also matter, but these come under the category of correct setup.

Set up optimally, the combination will have predictable handling. CanAm have posted videos and pictures of a large pickup with WD towing a large Airstream, on a skid pad, with all wheels (TV and trailer) in a drift. It is completely neutral. And that isn't because of the brand of WD, it is because of the setup.

By ignoring the importance of setup, you end up providing information that is wrong (or rubbish, in the words of some), and which can be downright dangerous. You should go back and read your study from the 1970s again, and your owners manual for your pickup. The answers are all there.

[waninae39]

i concur with @JCL
just look at the canamrv videos https://www.canamrv.ca/blog/category/hitch-hints/ and then think again

we have been using both Sway and WD , both have been very valuable and helped us especially on the highway

ie recently driving through Wyoming there has a large box in our lane, no one beside us, , my wife swerved to miss the box and get back in the lane. without sway control we would be in the ditch

without WD , we may have lost control of steering.
thus both are needed and valuable IMHO

[jcl]

Originally Posted by Andy543

This should be a standard test for anyone who wants to be in the trailer hitch manufacturing business. I'm not saying the hitch manufacturer should be required to pass this test, but they should be required to provide test results for their hitch on request. Then everyone will be able to see what they are buying.

The hitch manufacturer has no knowledge of your tow vehicle, your trailer, or your combination setup. But we each know our own equipment. While we may not want to do a skid pad test in order to calculate the cornering g force, it is straightforward (and a really good idea) to test our own vehicle combinations to see how they respond.

It is best practice, when the snow starts to settle on the road (or when it may be icy) for all of us to test our brakes. We generally do that on a straight stretch of road, sometimes right before a descent, so we know what we are dealing with. When towing, it is even more important.

I recall towing a large box trailer, with an SUV (within its ratings, if it matters), without WD (it wasn't my trailer), across the Rockies in winter. We hit a storm, with heavy snowfall. We checked the brakes a few times. When we came to a brake check point at the top of a major descent, right at the Rogers Pass summit (it was designed for semis) we pulled in, and tested the cornering performance in fresh snow. We also checked the emergency lane change response (it was a large empty brake stop). Much better to find out there, in a safe environment, than at the sharp corner at the bottom of the descent.

In the above example, our SUV had electronic Trailer Stability Control, but without separate control over trailer brakes. I tried to get it to activate, but couldn't do so. The combination was sufficiently stable, even with abrupt steering inputs, to not activate it. That told me what I needed to know about appropriate travel speeds under those specific conditions.

Instead of asking hitch manufacturers to provide theoretical test results (theoretical because they are not specific to your vehicle, trailer, or setup) it is perhaps a better suggestion for everyone to know what the emergency response is like for their own vehicle combination, under a variety of road conditions. We are each responsible for our own setup at the end of the day.

[Andy543]

Further to my previous post, here is an example of what can go wrong when you install a WD hitch on an undersized tow vehicle. The combination in question is a Toyota Tacoma towing a 30' Nash trailer. Now, the Tacoma is indeed a very good and robust tow vehicle, but I think everyone here will agree that it can't safely tow a 30' trailer. The question that arises is, who told this customer that he could get away with this? I suspect it was the trailer dealer, as this was apparently a brand-new trailer on its maiden voyage (I don't really know where the liability lies without more information).

Had the buyer showed up to tow this trailer away and hitched up without a WD hitch, he would have seen right away that this was dangerous. The rear end would be dragging on the ground and the headlights would be pointing at the sky. But, no problem. Throw a WD hitch on it. You'll be OK..... Famous last words. He should have come back with a bigger truck or renegotiated for a smaller trailer.

[jcl]

Originally Posted by Andy543

Further to my previous post, here is an example of what can go wrong....

That appears to be a very poor example.

1) Nash doesn't make a 30 foot trailer. What is the actual length of the trailer in your photo, or is it just something you found with Google?

2) What is the scaled weight of the actual trailer in your photo?

3) What were the conditions, especially with respect to crosswinds?

4) What was the travel speed when the (apparent) sway event started?

5) How was the combination set up? This is the same issue as your earlier posts. Setup matters.

6) While Nash don't make any 30 foot trailers, they do make one called an 18FM. It has an overall length of 23 feet. It has the same appearance as your photos. Nash advertise it as having the interior space of a 30 foot trailer, due to it having a large slide out. Coincidence? Could that have been the source of the confusion?

You are again blaming the tow vehicle, the trailer, and the WD hitch, without substantiation. More details please.

[Bobbo]

Originally Posted by Andy543

It seems that no matter how simple an explanation you give, there will always be someone there to deny it.

When you are wrong, yes. No one will try to convince YOU, but people who are just learning need to know that your information is, ummm, inaccurate.

Originally Posted by Andy543

Further to my previous post, here is an example of what can go wrong when you install a WD hitch on an undersized tow vehicle. The combination in question is a Toyota Tacoma towing a 30' Nash trailer. Now, the Tacoma is indeed a very good and robust tow vehicle, but I think everyone here will agree that it can't safely tow a 30' trailer. The question that arises is, who told this customer that he could get away with this? I suspect it was the trailer dealer, as this was apparently a brand-new trailer on its maiden voyage (I don't really know where the liability lies without more information).

Had the buyer showed up to tow this trailer away and hitched up without a WD hitch, he would have seen right away that this was dangerous. The rear end would be dragging on the ground and the headlights would be pointing at the sky. But, no problem. Throw a WD hitch on it. You'll be OK..... Famous last words. He should have come back with a bigger truck or renegotiated for a smaller trailer.

That is an example photograph of what can happen if you have no sway control. Trailer sway can do exactly that. A sway control hitch could have prevented that.

[uncle_bob]

Hi

As mentioned many many times, I can pop the WD / AS off of my F350 and easily demonstrate sway ( = oscillation that builds on it's own and can result in disaster ) at legal highway speeds.

This is not about "undersized tow vehicles" and it is not about "hitch manufacturer" propaganda. It's about folks not getting killed.

Bob

[gypsydad]

Agree with UB and JCL! Why Andy does not acknowledge the value of WDH and continues accuse the MFG of WDH systems of "false advertising" is puzzling for sure.

[Andy543]

Let me try to explain why it would be foolish for the OP to apply weight distribution to his setup.

The goal of weight distribution is to wind up with a level truck and trailer. I think most people will be OK with that. It is a rather controversial subject, though. Some people will argue that you should have more weight on the rear axle than on the front. Few, if any, however, would recommend having more weight on the front axle than on the rear axle.

Now, let's take a look at the OP's F-350. Unloaded, it will have about 60% of its weight on the front axle and 40% on the rear axle, i.e., in the unloaded condition, it has poor weight distribution. This is because it has a heavy diesel engine over the front axle, and an empty bed over the rear axle.

If you want this truck to ride level, you have to put more weight on the rear axle. Putting weight behind the rear axle will also take weight off the front axle, which will help achieve the desired levelness.

The OP's trailer will have a hitch weight of about 900 lbs. It happens that if you put 900 lbs. on a heavy duty truck's hitch ball, the truck will be very close to level, with a 50/50 front/rear weight distribution.

If you now install a weight distribution hitch and shift weight back to the front axle, the truck will again have a poor weight distribution. This is undesirable, because weight on the rear axle is necessary to provide stability to the rig.

Manufacturers literature will tell you to shift weight to the front, because they don't know what you are doing with the truck and they have to assume you are towing a trailer with the maximum allowable load. They would never recommend that you do that with a trailer of half the allowable load such as the OP's trailer, because that would unbalance the rig.

FALR (Front Axle Load Restoration) is a concept that manufacturers use to advise consumers how to level a rig. It is an imperfect metric and it is only used because they know most consumers don't have ready access to a scale. To get your weight distribution right, you really have to weigh your rig at a truck scale.

Sometimes you will hear a hitch salesman tell you that you need to buy their hitch because you will have poor steering, and you will get into an accident if you take load off the front axle. This is a complete myth. One of the world's best handling cars is a Porsche 911. It has 60% of its weight over the rear axle and only 40% on the front, and it has no steering problem. Some formula 1 cars actually have a 65/35 weight distribution, and they steer just fine.

Bottom line is, the OP should not use a WD hitch as it will only serve to make the rig un-level.

[jcl]

Originally Posted by Andy543

Let me try to explain why it would be foolish for the OP to apply weight distribution to his setup.

The goal of weight distribution is to wind up with a level truck and trailer. .....

The problem with your explanation is that you have missed what the actual goal of weight distribution hitches is. It isn't to wind up with a level truck and trailer, that is the visual cue, not the root problem. If that was all we wanted to fix we would simply use air suspension or something similar.

The goal is to restore front axle load so as to maintain handling performance. I wondered about your claims about hitch manufacturers, so I checked a few, and the first three all stated that the goal was to restore front axle load, not to level the combination. I stopped checking then.

You misunderstand what FALR actually is. You say that it is imperfect, and one needs to actually weigh the vehicle. That is how you determine FALR. What you are complaining about is using the proxy of measuring fender height.

Your Porsche 911 analogy doesn't work. That vehicle doesn't perform well because of the rear weight bias, it performs well in spite of it. Porsche has done an amazing job, but they can't overcome basic physics. The vehicle has a very high cornering limit, so many won't reach it, but if they do, drivers can be surprised by the transitions from oversteer to understeer in a corner, depending on throttle and brakes. Porsche has done all sorts of things to raise the cornering limits, including using different tire sizes front and rear.

And in your whole message, you ignored all the points about sway bars, focusing only on weight distribution.

[uncle_bob]

Hi

I can *put* a real world 30' AS trailer on a real world F350 without any WD. Been there done that.

I *know* what happens and it most certainly is *not* an improvement in handling.

Bob

[gypsydad]

Originally Posted by jcl

The problem with your explanation is that you have missed what the actual goal of weight distribution hitches is. It isn't to wind up with a level truck and trailer, that is the visual cue, not the root problem. If that was all we wanted to fix we would simply use air suspension or something similar.

The goal is to restore front axle load so as to maintain handling performance. I wondered about your claims about hitch manufacturers, so I checked a few, and the first three all stated that the goal was to restore front axle load, not to level the combination. I stopped checking then.

You misunderstand what FALR actually is. You say that it is imperfect, and one needs to actually weigh the vehicle. That is how you determine FALR. What you are complaining about is using the proxy of measuring fender height.

Your Porsche 911 analogy doesn't work. That vehicle doesn't perform well because of the rear weight bias, it performs well in spite of it. Porsche has done an amazing job, but they can't overcome basic physics. The vehicle has a very high cornering limit, so many won't reach it, but if they do, drivers can be surprised by the transitions from oversteer to understeer in a corner, depending on throttle and brakes. Porsche has done all sorts of things to raise the cornering limits, including using different tire sizes front and rear.

And in your whole message, you ignored all the points about sway bars, focusing only on weight distribution.

Great explanation! Not sure if Andy agrees or understands, but clearly WDH restores the weight back to the front axle (control) as is shown in numerous videos why this is important for control while towing. IE the name...WDH= Weight Distribution Hitch. Hey, clearly there are some "different" folks here..."lead the horse to water, but you can't make him drink!"

[Profxd]

The basic point Andy543 makes is that if you don’t feel safe driving your TV and RV trailer at 55 mph without a WDH, using a WDH may not make you any safer. This by all means true.

[DKB_SATX]

Originally Posted by Profxd

The basic point Andy543 makes is that if you don’t feel safe driving your TV and RV trailer at 55 mph without a WDH, using a WDH may not make you any safer. This by all means true.

... may not make you FEEL any safer...

[FMSports]

Tacomas I've been in are garbage for handling/dynamics. I wouldn't tow anything of weight with one. Having said that, if the trailer sways, it's a trailer problem.. that becomes a problem for the TV driver.

Why does a lifted 2500 series truck handle a swaying trailer better? I've only driven a 2500 once it was big and burly but it's dynamically worse imo. Sure there is more beef resist push.

If you're not a good driver, get a better driving TV.


Tacoworld info:
Looks more like a Nash 22H--24'9" O.A.L. 4,222 lbs. dry. You cannot believe a thing the media reports...

[Profxd]

Something to think about in this debate. Why is it that the RV travel trailer is about the only trailer type that a WDH is a must? Look around at all the utility, cargo, car haulers, and other trailer types being towed and notice none of them are using a WDH. So why? I’d love to here people’s opinions on this.

[jcl]

Originally Posted by Profxd

Something to think about in this debate. Why is it that the RV travel trailer is about the only trailer type that a WDH is a must? Look around at all the utility, cargo, car haulers, and other trailer types being towed and notice none of them are using a WDH. So why? I’d love to here people’s opinions on this.

Utility trailers are usually pretty light.

Car trailers generally have a lower profile, so less wind impact, and it is straightforward to adjust vehicle position to shift tongue weight. The only ones I have seen WD on are enclosed car trailers.

Boat trailers generally have a long tow arm (axle to hitch ball) as the bow of the boat is much lighter than where the engine is located. This is also why boat trailers can have 5% tongue weight.

Large box cargo trailers are the only ones I usually see WD hitches on, apart from travel trailers.