Trailer Towing With A Friction Sway Control Vs WDH

[SKLau]

Below is a message that I posted sometime ago under an old (and long) thread. Since there has been limited response so far, I thought I may just edit and repost it as a separate thread so that it will no longer be buried in page 3 of the old thread in order to get some additional exposure .

I tow a 24 feet camping trailer with a weight of about 4500# using my 2005 V8 LR3. I am currently using an EZ-LIFT friction sway control system and found that there is a significant difference in the sway behavior with or without the friction sway control bar. However, I am still not totally happy with the friction sway control system particularly when there are cross winds. I find I have to keep my speed at 50 mph or below to avoid the "white knuckle" driving experience.

I have often heard people said that the automatic air suspension system on the LR3 can level the trailer/truck system just as effectively as a WDH system. However, I have also been told that even though it does a good job in leveling the traile and truck, it does not tranfer part of the trailer weight to the front truck axle like what a WDH system does. With the help of some towing experts on the RV NET.com, I did a calculation and found that with my HTT hooked up to the truck, more than 790 lbs of load is added to the rear axle of my truck while the front axle is now about 220 lbs lighter. As a result of this weight change, the steering and handling of the truck could thus be adversly affected. This plus the other fact that the manual for the friction sway control bar specifies that the bar should be removed when the road is wet make me want to seriously assess the possibility of using a Weight Distribution Hitch, such as the Equalizer WDH/sway control system or a Reese Dual Cam system, for improving my towing safety.

As we know, the LR3 manual says that a WDH should not be used on this truck. However, like many others, I have not been able to get a reasonable explanation from Land Rover on the reason why we should not use the WDH on LR3. After numerous attempts trying to find the right people from LR for help, the best I could get directly from LR a year ago was that they have not tested the WDH on this truck and therefore all LR3ers should not use it (humm....). I have also heard from some people (not directly from LR) that a WDH system would interfere with the automatic air leveling system and make it confused. The question is then there are many other trucks on the market that also have automatic air leveling systems, so why there's no problem with these trucks? Again, I have not heard any reasonablle explanation for this.

It would thus be very helpful if some of our fellow LR3ers who have actually been towing with a WDH could share their experience with us. So far I have only found very few reports from people who have done that. The posting from a poster "FloridaLR" on this forum said that after a short 30 mile trial, he did feel it affected the smoothness of his ride and decided to remove it. However, another poster on the RV Net.com reported that he was getting great performance with a WDH on his LR3 after thousands of miles. So, what is the verdict?

I welcome the comments from anyone.

 

[schafari]

I tow a 23' total length lightweight Starcraft trailer. IT is about 450lb tongue and 4000lb total weight. The trailer tows like a dream, and I am new to an SUV and have never towed before. I have yet to have a white knuckle experience. The truck weighs 6K lbs, and I think this has something to do with it.

I use a Reese friction sway control on one side. I do not use a WDH. Frankly, the trailer seems locked in position and I really never experience sway at all. This is in Texas and Olk. Not to many challenging hills, but the wind can be brutal. Even with semi passess and winds, no problem.

I drive at 65MPH in 70mph zones most the time with zero problem. In a couple of instances, I have had to pass, and it travels fine at 75mph.

If you can't drive more than 50mph, I would say something is wrong, and/or you have are underestimating the weight of the trailer. If you hitch weight is truly 790lb, you are about 50% over the limit. That is a huge no-no. Could be your set up also. What is your drop? Is your trailer level when hitched? Are your tires on your trailer in good shape, balanced, aligned, etc.? How do you load your trailer? Is weight to one side rather than the other? How do you load the LR3 in the back seat and cargo area?

One great thing about the LR3 as a tow vehicle other than the mass of the LR3 itself, is the short overhangs. My trailer hitch cup lip is mere inches from the rear bumer. It is very close to the bumper, which is relateviely close to the rear axle. That is good.

I would not do a WDH. The air suspension will continue to try to counteract the forces the WDH is constanly redistributing as you drive down the road. The CPU will get confused and the compressor overheats. . . That is what has been said anyhow, and it seems logical.

Finally, I am not sure where you heard that you shouldn't use a sway control in wet conditions. That does not seem to make sense at all. Perhaps when backing up in wet conditions. . .

 

[joey]

I will admit I have not towed with an LR3, but I will say this... if you plan to tow anything longer than 22 feet I would not do it with out a WDH of some kind. I have been towing with vehicles for years and would not consider it with a short wheel base vehicle to be towing without a WDH.

There are lots of vehicles on the road today that use WDH and air suspension... NO issues.

Take just about every Semi on the road... they almost all have air suspension and depending on if the driver has a clue the load may or may not be adjusted correctly. And they still drive down the road... may not be the best offering of knowledge here, but I will say when I do go to tow with my Rover and pull a camper it will have a WDH... Keep in mind LR also say no to WDH on non-air suspension models....

 

[SKLau]

Safari, thanks for sharing your experience with me. Your truck/trailer combination is quite similar to what I have. However, it is very interesting that your towing behavior appears to be very different.

To answer your questions, 790 lbs is the load added to the rear axle of the truck when the camper is connected. This is different from the hitch weight. The hitch weight, as actually measured on a scale, is 450 lbs, just like yours. This tongue weight is thus lower than the maximum allowed. The weight of the camper is between 4200-4500 lbs depending on the load that is carried (I normally tow with less than 200 lbs of gear in the camper, mostly at the front and with empty fresh, grey and black tanks). If one follows the 12-15% tongue wt/trailer wt ratio rule of thumb, this tongue weight is actually slightly less than the recommended optimum value for safe towing. I have checked most of the other things that you mentioned also. The truck/camper combination appears to be very level (as expected with the air suspension system), the truck and all the tires have only 13,000 miles on them and look good. The tire pressures are at the factory recommended level for towing (33 psi at front and 42 psi at back). We usually have only two people in the truck, I have nothing on the back seat except our 10 lb little dog, and carry less that 100 lbs of gear in the trunk. So, I am at a loss.....

As for the no wet use restriction of the friction sway bar, it is not something that I heard from anyone, it is written in black and white in the instruction manual that came with the EZ-LIFT. You may want to take a closer read of your Reese manual to see if there is also a sentence like that buried somewhere or not. If not, your design could be different.

Joey, your advise on the need of a WDH is exactly what I have been hearing from almost everyone from the RV NET Forum who are experinced in trailer towing. That's the reason that makes me concerned about the safety of my set up. I really would like to install a WDH on my trailer. However, I wanted to seek some feedback from fellow LR3ers who have the actual experience of towing with a LR3 using a WDH before I decide. Specifically, I am very interested in finding out whether it is true that the use of WDH is really causing erratic behavior of the air suspension system, and may even lead to its overheat.

Your observation that LR also says no to WDH on non-air suspension models is a very important one. Is this listed in any specific LR manuals that you know of? This is something that I was totally unaware of before. In fact, I thought all LRs are equipped with the air suspension system. If LR indeed specifies that WDH should not be used on non-air suspension models, this would change my thinking significanly. The supposedly "interference with the air suspension system" explanation that we have been hearing would no longer hold much water. Wouldn't it? Then the risk that one takes for installing a WDH on LRs may just be that LR has not tested the WDH on their trucks. No test data is quite different from knowing that it is bad. Based on the fact that most other trucks with air suspensions have no problem with WDH, the risk of using one on LR3 doesn't look too big then. Any thoughts from anyone?

 

[schafari]

On page 214 of my 2005 manual it states that "an equalising or other form of weight distributing hith should NOT be used with your vehicle." Although there is a lot of great info on the RV forum, I would consider many other sources as well.

Our setups sound almost exactly the same. 15K miles usually one or two people, limited gear, and empty tanks. . . I am one of those people that are likely a bit to obsessive or worried about things, and I had no experience towing. Towing with this combo is a joy. The only thing I don't like, is going up big hills with the RPMs kicked up into 4.5K.

The reason I say this, is there has to be something off on your rig. I pass semis, they pass me, wind, no wind, it all pretty much feels just like I just have the truck, not a 23' camper attached. Not much help I know, but if you can't go over 50mph, and I have no problem with 65mph-75mph, while on conference calls, while tending to two babies in the rear. . .believe me, it is not my skill which is near zero being a newbee to towing, it has to be in your rig.

 

[Airboss]

I'm surprised that there hasn't been more discussion on this topic. Are there no more than 3 or 4 LR3 owners that tow travel trailers? I was hoping that there would be some kind of resolution as I am very interested in buying a trailer myself and I'd like to be as prepared as possible.

 

[SKLau]

Your observation that LR also says no to WDH on non-air suspension models is a very important one. Is this listed in any specific LR manuals that you know of?.....If LR indeed specifies that WDH should not be used on non-air suspension models, this would change my thinking significanly. The supposedly "interference with the air suspension system" explanation that we have been hearing would no longer hold much water.

Just talked to a sales professional at my local LR dealer. He pulled out an owner's maunal on a Land Rover Discovery that did not have an air suspension system and indeed there was the same instruction that an equilising or other form of weight distributing hitch should not be used on that truck. Again, no explanation was given. However, I think this is sufficient proof that the restriction on WDH from LR has little to do with the "conflict with automatic air suspension system" that many of us have heard or been led to believe. So what's the actual technical reason? Is it just because LR has not gotten around to test it on their trucks in UK? Why is it so difficult to get the explanation from LR? I am with Airboss, many of us would like to have a resolution instead of making various guesses on our own.

By the way, the person that I spoke to at my LR dealer happened to be someone who used to operate a trailer hitch business before joining LR. He told me that he couldn't think of a good reason for this restriction. In fact, he said he had installed a numbers of WDH systems on LR Discoverys in his days (w/o knowing the restriction at that time) and had not heard from anyone came back to complain. He said in his opinion, I could put on a WDH and use it as long as I don't try to pull the trailer to some difficult places such as off-road trail heads.

Any thoughts from anyone?

 

[grommet]

SKLau, there is only one manual for a Discovery 3 or LR3. Sorry, no special coil suspension only manual. LR documentation is far from perfect, so I don't think that is any proof of anything.

FYI: I've never used a WDH on LR3, for the few times I've need to pull something... but I've never exceeded 5000 lbs., and have never attempted to tow something that exceeded the official tongue weight limit.

If you really want an answer, call up customer service and attempt to escalate the question. Maybe you'll get an official statement from a higher up tech. Maybe not. The only official statement is we have so far is "don't use it." Maybe they think that's enough.

 

[SKLau]

Thanks, grommet, for pointing out that there is only one manual for Discovery 3. Based on that, I have the following thoughts.

First of all, I don't know if Discovery 3 trucks are: (1) all equiped with the coil suspension only or that (2) some of them have the air supsension as an option. (I am sure many of you out there could answer this question).

Now, if the answer is (1), then my earlier deduction that the WDH ban has nothing to do with the air supsension operation is a valid one.

On the other hand, if the answer is (2), my next question is then whether there is an added statement in the maunal specifying that the WDH ban is limited only to those models that have the air suspension system option. If not, an average owner would have no choice but take the instruction to mean that this ban applies categorily to all trucks, with or without the air suspensions. That would lead one to the same deduction that the WDH ban is not due to the air suspension system, (unless the manual was written so casually that it did not bother to differentiate this even though the coil suspension ones might have been OK to use the WDH... had air suspension been the reason for the ban.)

Based on the above analysis, one would have sufficient reason to deduce under both situations that the air suspension interference issue may not be the actual cause for the WDH ban. Other than the "we have not tested the WDH on LR3" reason given to me by an offical LR customer service person, I have yet to hear any additional reasonable explanation. Believe me, I have tried many times and many ways attempting to get an answer, including my LR dealer, LR customer service, LR technical reps, towing experts, hitch installers....Has anyone else had gotten another explanation from an official LR customer or technical service reps on this?

I believe that not getting a clear explanation is probably why there are a number of LR owners who have decided to install WDH on their LRs anyway disregarding the statement on the manual. Their logic is that since most of the other domestic or foreign trucks on the road towing a trailer could use a WDH, why couldn't their LR? I highly doubt that many of these people would risk the safety of their families if they knew or understood that there was a safety reason for not using a WDH.

My concern is whether there is a structural design thing that prevents the use of WDH on LR. If that is the case, I am sure that many of us would like to know what it is. It will help all of us greatly if this could be clarified as soon as possible before more people trying to take things in their own hands attempting to install WDH on their trucks. If the "we have not tested WDH on LR" is the reason, then let us know also.

I got my LR3 with the full intention that I would be using it once a while for towing my 24 ft camping trailer and I had told my LR dealer right upfront about this. But I had no idea that I could not use a WDH with this truck until after I got the truck and read through the two hundred page maual. I like my LR3 for my daily driving, it is a great truck, but I also wish that I could use a WDH on it for better and safer towing.....

 

[CoreyS]

While I've never towed with my LR3, or with any other vehicle with air suspension, I do have a lot of experience towing various sized trailers on a Chevy 2500HD with and without a WDH. And, as being a engineer, my thoughts are these:

1. I can't imagine that the air suspension is the limitation for not using a WDH. With 500lbs of tongue weight at the rear of the vehicle, or evenly distributed over both axles (as with a well setup WDH), I don't think the air suspension would care. That amount of weight should be well within the gross axle weight ratings.

2. As someone else has commented, it could simply be that they have no tested a WDH on the LR3, and therefore cannot recommend their use.

3. Lastly, the trailer hitch receiver on the LR3 is a little goofy, and its design may not be capable of handling the different forces/torques that a WDH applies to the hitch. A WDH applies a torque thru the trailer hitch receiver (with the ball as the pivot point), to transfer load to the front axle, which is opposite (but of smaller magnitude) to the torque applied when no WDH is used. Perhaps the receiver cannot handle this load, or perhaps the security of the locking pin is reduced, or something.

Anyway, there's my fuel for the fire. By the way, I am a big fan of WDH's to increase stability and safety while towing.