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I do not disagree with you. However, instead of worrying about lawyers, I prefer to set up a proper TV/TT combo. I am not one of so-called payloaders. IMO proper weight distribution, proper sway control, max axle ratings, max tires ratings are so much more important than being withing the payload spec.

I have no doubt (absolutely no doubt) that my combo is more secure (stable, with better braking power, etc.) that ANY half ton truck with such trailer. I just can't take that much crap in the back of my car, as the truck owners can.
 

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Gents, the Can Am thing really isn't a good idea for the Treg. You are paying someone to screw with a design that was tested and developed by real engineers, over several years, and who knows how big of a budget.
I am a structural engineer. Well I didn't take the PE exam because I got sidetracked by a career in software, but I took all the courses (and a couple grad level courses in it for fun).

The issue the Can Am modification is trying to address is the hitch's ability to transmit torque. Normally this isn't a problem with a ball mount because the ball doesn't transmit torques (trailer rotating relative to the car). It's a freely rotating joint, so only transmits forces (forward/back, left/right, up/down) from the trailer to the car. One of the reasons to use freely rotating joints like pin joints and ball joints is that the lack of torque vastly simplifies the design process. Normally you have to solve 6 equations (force in 3 axes, torque around 3 axes). The ball joint sets all the torques to zero, leaving you to solve just 3 equations thus making it tremendously easier (sometimes even trivial) to solve for the forces which the structure has to withstand.

If you use a WD hitch, it is locking the trailer to the car in the pitch axis, and suddenly the hitch is transmitting torque to the car via the hitch mount every time the trailer tries to pitch. Since Europe doesn't use WD hitches, this is a configuration which is never supposed to happen. And so VW engineers never did the calculations for what happens when the hitch suddenly starts transmitting torque to the Touareg's body. This is why VW says not to use a WD hitch - they simply don't know what will happen. (Anti-sway devices do the same thing in the yaw axis. But they have more give since you need to be able to turn, so the torques generated are a lot lower.)

Now, it might be safe to use a WD hitch. When you use freely rotating joints in the design, the torques get converted into forces and so your structural members end up having to be a bit stronger than if you used a rigid structure. So it's possible the beefier car body can handle the introduction of torque via the hitch just fine. But nobody knows for sure because it was never considered in the design.

The weak point is how the hitch is mated to the car's body. To resist torque, you need leverage. The ideal method to mate the two would be for the hitch to have long arms which fit inside or alongside the lengthwise beams in the car's frame, and to bolt or weld the two together. If the hitch tried to twist (trailer tried to pitch up/down relative to the car), then these arms would provide plenty of leverage to resist that twisting.

But that's not how the Touareg's tow hitch is connected. It's mated to the frame via 8 bolts all in a single plane. Torque transmitted through the hitch gets converted (best case) into compression on half the bolts, tension on the other half; or (worst case) shear forces in the bolts. The latter is what's worrying. With a WD hitch, you're basically using the length of the car and trailer like they're two long arms of a bolt cutter, and when the two twist relative to each other you're applying all the torque generated by those two long arms to the 8 bolts sitting right at the fulcrum holding the hitch onto the car. The length of the car and length of the trailer, vs the length of the bolts is a huge amount of mechanical advantage, creating huge shear stresses for the bolts to resist.

The Can Am modification attempts to reduce this mechanical advantage by welding on a long arm from the hitch to the body frame. This arm is considerably longer than the bolts. So when it resists the torque between the trailer and car, the car and trailer have considerably less leverage. The arm is able to transmit most of the torque from the hitch to the car body, reducing the shear stresses on the bolts.

For an intuitive sense of what's going on, imagine you're holding a baseball bat by cupping the small end of it with your hand. The length of your fingers on the end of the bat is very short relative to the length of the bat and your arms. This corresponds to the bolts being very short relative to the length of the car and trailer. Holding the bat this way, it's still fairly easy to move the bat around as long as you allow the bat to swing freely (what a hitch ball does). Your fingers (the bolts) can easily resist the forces generated by moving the bat around.

But now try moving the bat without allowing the bat to rotate. That's what a WD hitch does - resists allowing the trailer to pitch relative to the car. Now your short fingers have to generate a tremendous amount of torque to try to keep the bat from rotating. And a sudden movement of the bat could cause your fingers to lose their grip (bolts to snap) and your hand (car) would lose its hold on the bat (trailer).

What the Can Am modification does is equivalent to you putting a second hand further up the bat. Now you're holding the bat by its end (bolts) and further up the bat (Can Am mod). This greatly reduces the leverage the bat has on your grip, making it a lot easier for you to hold the bat in the same orientation as you move it around. Is the mod really necessary? I don't know, you don't know, and VW doesn't know. But by reducing the increased stresses on the bolts introduced by a WD hitch, the mod makes it much less likely that they'll suffer a failure due to the WD hitch.
 

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The problem with the above is it is a solution looking for a problem. The Can AM modification doesn't feel any forces going through it at the loads we are using (within the designed capacity) because the bolts and hitch attachment have zero flex and we're substantially over engineered from the start. The specs on the bolts in question are very high (100,000 lbs +? For M12 1.5 10.9 bolts-exact specs are not easily found by me--but way over the max amount ever seen in a dynamic load setting with the tiny amount I am able to transfer using my style of WD).

You are right about what you are saying, but none of us are anyplace near 3,000 lbs on the tongue...if memory serves this is where the calculations put the bolts in critical stress at 1 million oscillations.

I would also argue VW knew full well that folks would run WD on this and that it WAS engineered to handle it. The last thing they want is brand erosion from a common product used in towing on a vehicle called the tow rig. Proof of this is my Tregs later years hitch has with and without WD figures on it.
 

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Spiegelglatt


. Proof of this is my Tregs later years hitch has with and without WD figures on it.
Is it a VW OEM hitch?
Could you please post the values for with and without WD values.
 

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Thanks Solandri for jumping on this topic.

“It's mated to the frame via 8 bolts all in a single plane. Torque transmitted through the hitch gets converted (best case) into compression on half the bolts, tension on the other half; or (worst case) shear forces in the bolts.”.
This is interesting part for me – similar design with BMW X5 (E70/F15), i.e. 8 bolts holding the hitch. See below Mercedes GL/GLS hitch. As a part of the assembly, it has two arms, which I understand are bolted to the chassis.



The first generation of BMW X5 (E53) had similar arms (shorter than Mercedes). The next generations do not use the additional arms for the hitch. The towing capacity was not decreased. Definitely, from the first to the second generation they made the chassis stronger (official BMW materials).

I am wondering whether due to the overall strength of the chassis, BMW engineers came to the conclusion that the additional arms are not needed? I am not engineer, but I understood that there is huge strength margin on the bolts. I also understood from what I was reading online that actually the hitches of the German SUVs are the weakest points (some failing – Mercedes, some flexing close to the receiver due to the long drop plates between the receiver and the main hitch tube – other German brands).

I did the Can Am reinforcement on my BMW X5 and will do this on the next tow vehicle, which will be likely Mercedes GLS as there are no known problems related to this mod.
 

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With the Can Am ''solution'' for the Touareg, I wonder how it will possible to remove the muffler to get access to the AdBlue tank and the DEF heater ?
 

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With the Can Am ''solution'' for the Touareg, I wonder how it will possible to remove the muffler to get access to the AdBlue tank and the DEF heater ?
You cannot, as they usually weld it in place. The end. Cut it off to gain muffler/ad blue access.

UNLESS, you request that they create a mount using a bolt through system to remove the strengthening brace when needed. I know that one exists, I've seen pictures of it. Probably costs more too.

I was led to contact Can Am to get my Touareg modified last year, but even though the reinforcement would have been done "free" by the company that made my trailer, it would have resulted in loss of warranty for sure, because the reason to do the reinforcement is almost always to compensate for a tongue weight that exceeds the limits of the Touareg receiver (770 pounds).

Even if the Touareg CAN pull a heavier trailer than rated, there's no rational reason to modify the Touareg to make it "safe/safer". Just don't pull trailers that exceeds the tow vehicle capabilities.

My receiver sticker declares 616 pounds max tongue with AND without a WD hitch. SO VW has made changes to how they view weight distribution in the US market, but still sticks with the 8% rule for tongue weight vs tow capacity (7700 pounds X 8% = 616 pounds). BMW, Mercedes, etc, check their tow limits, they all use the exact same formula.
 

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Any grounds for saying that? I had an engine replaced in my car under warranty, with the hitch reinforcement. They need to actually take the whole hitch with the reinforcement down in order to get the exhaust system down. No questions asked.

(...)

I was led to contact Can Am to get my Touareg modified last year, but even though the reinforcement would have been done "free" by the company that made my trailer, it would have resulted in loss of warranty for sure, because the reason to do the reinforcement is almost always to compensate for a tongue weight that exceeds the limits of the Touareg receiver (770 pounds).(...)
 

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My grounds are this. Warranty claims are at the sole discretion of the dealership. If they "feel" that you have made any modification that has changed your vehicles reliability, they can deny warranty coverage. It will then be your responsibility to prove your changes did not have a direct affect on your vehicles failure.

My conversation with the Can Am service manager (Dave) was specifically about warranty coverage, and he agreed that if my dealership, or any dealership, wanted to void my powertrain warranty (10yr/100K) because of the receiver reinforcement that it would be their (the dealerships) call. This kind of modification does void the warranty, and it depends ENTIRELY on the dealership if they will or will not cover a repair for anything they could claim.

If your dealership decides that you were towing something too heavy (even if you weren't) then they can point at the receiver reinforcement and claim it cause XYZ issue (transmission, driveshaft, CV Joint, cooling problem, etc). Now the problem is yours to PROVE it wasn't from towing a too heavy load.

I guess it all comes down to the relationship you have with your service department. I wouldn't take the risk involved. My trailer was towed back to the factory, and over the course of 5 weeks, they modified the trailer axle locations to bring the tongue weight in line with the claims that had been made. I had documentation of their claims.
 

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Classic FUD (fear, uncertainty and doubt). "Warranty claims are at the sole discretion of the dealership." - this is not correct. if the manufacturer (not dealership) would like to void warranty, this would be the manufacturer not me to prove that the modification was a root cause of the problem. Simple as that.
 

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Here you go:

Hitch is OEM, was purchased from dealer as the truck was not equipped with receiver as an option when new.
Spiegelglatt, very interesting! This is the first I've heard or seen of anything official from Volkswagen that appears to allow weight distribution hitches. What year is your Touareg and where are you located?
 

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Spiegelglatt, very interesting! This is the first I've heard or seen of anything official from Volkswagen that appears to allow weight distribution hitches. What year is your Touareg and where are you located?
My Tregs are a 2007 with a hitch purchased around 2012 from a dealer and a 2008 with factory tow package. Both hitches are the same part number (the one that came installed on the Treg and the one I purchased.).

I think this is a common hitch label though??? Both mine are like this...
 

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Doesn't matter what you tow with, being safe and understanding what you are towing is most important.

Most folks do the full size truck to tow just about anything, and if that works for them that is great. However, many of these same folks have to deal with instability, sway, terrible braking, and really get worked up with towing because the full size trucks advantage stops with size and ratings. (These are the people who are petrified by wheel base length, sway, and transmission issues or transmission coolers, or suspension airbags for sag). If you want to enjoy towing and not have to stress (once you are setup) the Treg is your ticket as it came from the factory ready to tow. I can't tell you how many folks in full size trucks have commented on how there is no suspension sag when I am hooked up, or saw me on a hill climb and stop to chat about what is under the hood.

I have been in several situations that underlined the Tregs towing prowess, be it high winds, emergency braking, or rapid acceleration to merge with traffic...all met with outstanding results. For the small weight (7,500 lbs) that I tow, I couldn't ask for a better tow vehicle. Obviously full size trucks have a place when properly outfitted, but I don't have the need for that.
Hi, your comments are interes. I’m a newbie to Treg towing and still in the middle if I should use WD and anti sway device. We do not have air suspension in our 2015 Treg Sport TDI V6 with towing package. Our trailer is a dual axle 22.6’ total length, 3650 lbs dry, 6K gross Wt and 420 tongue wt. Given these numbers, is WD /anti sway units necessary? Any thoughts?
 

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I know there are several blogs but I’m still undecided to use WD or not. I would appreciate any comments if WD /anti sway device is necessary on our 2015 Treg Tow package with no air suspension. Our trailer specs are attached. Any thoughts anyone?
I just picked up a camper that has a similar dry weight (3,400#) and tongue weight (450#). I hauled it "empty" and it felt great behind my '10 TDI on steel springs. I only drove 55 mph due to older tires, but there was no sway, no dip, nothing. I'll try it loaded for a trip in the spring before I decide on whether to use my WDH from a previous trailer. The camper is a single axle, and has more tongue weight than my boat, which is a dual axle trailer. That camper, being a dual axle, may be similar.

You can get anti-sway, WDH, or a combo. I would try pulling it before you spend the money on either.
 

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I just picked up a camper that has a similar dry weight (3,400#) and tongue weight (450#). I hauled it "empty" and it felt great behind my '10 TDI on steel springs. I only drove 55 mph due to older tires, but there was no sway, no dip, nothing. I'll try it loaded for a trip in the spring before I decide on whether to use my WDH from a previous trailer. The camper is a single axle, and has more tongue weight than my boat, which is a dual axle trailer. That camper, being a dual axle, may be similar.

You can get anti-sway, WDH, or a combo. I would try pulling it before you spend the money on either.
Thank you. We decided to get the weight distribution hitch without the anti sway for now. I’ll post as soon as we take it loaded on the highway in the spring.
 

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Here you go:

Hitch is OEM, was purchased from dealer as the truck was not equipped with receiver as an option when new.
Thank you for posting this photo. The sticker on your OEM hitch is identical to the one on the factory hitch that my 2016 Touareg TDI had when I bought it, except for the max tongue weight, which is 616 on mine. Everything else is the same, including the where it was made in the bottom left and the part number in the bottom right (don’t know what to make of the 21/10 on yours versus the 23/15 on mine). I find the 770 on yours more plausible since it is exact 10% of the towing capacity of 7700 but don‘t understand why they would show it as 616 at a different time. Since my Touareg is a 2016, it may be that 23/15 refers to a time in 2015 when it was made. Maybe 21/10 refers to a time in 2010 when the OEM hitch on your Touareg was made. If so, why would they decrease the max tongue width from 770 to 616 which happens to be exactly 8% of 7700 a few years later? Was it a ploy to dissuade people in this country from using WDHs or towing larger trailers? I recall seeing a few posts here by other members saying they were waiting to get a new sticker from VW saying 770, but that would mean the sticker with 616 were a mistake, and only fixed when a Touareg owner pursued this matter with VW. I sure would appreciate any insights you can offer since I want to be safe towing which includes not exceeding the max limits, so the difference between 616 and 770 is in fact material to my thinking. Thanks very much for your help.
 
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