Are They Meaningless? Tow Limits, Payload and Axle Load

[jcl]

Originally Posted by gypsydad

Lets see...do you have a false sense of security purchasing a TV with decent payload, power, braking, transmission, suspension, and cooling system set up for HD towing by the MFG?

Let's use the example of a new F250, crew cab, short box, without the Tremor package. With specific options from the manufacturer, that vehicle is listed as being able to tow a 20,000 bumper pull trailer (eg conventional hitch, not one mounted on the bumper). It is listed as having that capability for a weight carrying hitch, eg no WD equipment. The towing guide recommends WD equipment, and a specific FALR number, for any trailer over 5000 lbs, but that is in the fine print.

New purchaser comes along, buys that truck, puts a 10,000 lb Airstream behind it, and thinks to themselves, this is only half the rated towing load, so I don't need any of that fancy WD stuff. They are less likely to confirm loads on scales. They find that they have plenty of power, so they can tow at higher speeds. The truck isn't safer at higher speeds, but it provides less feedback to the operator, so they can find themselves in a situation where they don't know they are reaching a safety limit such as roll over or trailer sway until they exceed it.

That hypothetical purchaser has just fallen into the trap that you very clearly illustrate. Thank you for that. You said "that was set up for HD towing by the MFG" The manufacturer didn't set anything up. That is up to the owner. And that owner can be led to believe that set up is less important, when many of us suggest that it is the single most important thing in operating a safe combination.

I read on this forum of a purchaser of a RAM 2500 who said he didn't need WD or any "fancy hitch" because he was towing a negligible weight (9000 lbs) compared to his 18,000 lb tow rating. Balderdash.

[jcl]

Originally Posted by gypsydad

..do you have a false sense of security taking a passenger vehicle, not designed as a TV, to someone and have him "modify" by adding a trailer hitch for an AS taking limits beyond the MFG specs (no modification to brakes, cooling, transmission, suspension) for said vehicle....? Do you feel lucky or what!

The modifications I would make to a vehicle otherwise capable (sufficient axle and tire ratings, reasonable powertrain, high performance brakes, etc) would be for a strengthened receiver hitch that was customer designed for the specific vehicle. I don't consider such a course of action to rely on luck.

I would know that the vehicle had a lower CoG, with four wheel independent suspension, and thus better handling/stability than an archaic design with solid axles, one often lifted for style reasons, at the expense of performance.

I would have more ability to avoid a crash, especially when hitched, than simply relying on the mass of the vehicle I was operating to survive a crash or damp out feedback from the trailer.

I don't consider this feeling lucky, I would have used words like informed, due to both specs, and my own test results. The fact that the manufacturer of the vehicle didn't decide to go down the path of validating this combination doesn't particularly bother me. I can see their logic, they wouldn't expect to sell many.

[gypsydad]

Originally Posted by jcl

The modifications I would make to a vehicle otherwise capable (sufficient axle and tire ratings, reasonable powertrain, high performance brakes, etc) would be for a strengthened receiver hitch that was customer designed for the specific vehicle. I don't consider such a course of action to rely on luck.

I would know that the vehicle had a lower CoG, with four wheel independent suspension, and thus better handling/stability than an archaic design with solid axles, one often lifted for style reasons, at the expense of performance.

I would have more ability to avoid a crash, especially when hitched, than simply relying on the mass of the vehicle I was operating to survive a crash or damp out feedback from the trailer.

I don't consider this feeling lucky, I would have used words like informed, due to both specs, and my own test results. The fact that the manufacturer of the vehicle didn't decide to go down the path of validating this combination doesn't particularly bother me. I can see their logic, they wouldn't expect to sell many.

Well, your obviously smarter than most of us here? None of us have ever considered the obvious advantages of modifying a vehicle with such great handling characteristics such as you describe. Although, many of us here also own MBZ, BMW, Audi, Porsche, etc; not sure why we would want to modify any of these to do a job towing beyond their payload or other spec ratings to do a job they were not designed/intended. If something happens while I am on the road, there are several dealers that can help me; I don't have to have someone in Canada on speed dial....just saying, it's all in how you want to roll...

[jcl]

Originally Posted by gypsydad

Well, you're obviously smarter than most of us here? None of us have ever considered the obvious advantages of modifying a vehicle with such great handling characteristics such as you describe. Although, many of us here also own MBZ, BMW, Audi, Porsche, etc; not sure why we would want to modify any of these to do a job towing beyond their payload or other spec ratings to do a job they were not designed/intended. If something happens while I am on the road, there are several dealers that can help me; I don't have to have someone in Canada on speed dial....just saying, it's all in how you want to roll...

No, I don't think I am smarter than everyone. There are obviously some knowledge gaps among posters though, so I am simply providing information.

Firstly, what you refer to as modifying a vehicle, I refer to as installing a custom receiver hitch. And installing clip on towing mirrors.

The whole thread has addressed the issue of whether tow ratings are maximized in all markets, or reduced in some markets such as North America. No need to rehash that. No need to exceed load ratings for tires and axles. Our previous generation X3, built on a 3 series platform, had more carrying capacity, by hundreds of pounds, than a friend's RAM 1500. It also had more hp, better brakes, less rear overhang, and better handling. It was only offered with a 3500 lb hitch by the manufacturer, but aftermarket hitches can quickly resolve that issue.

Here is an obvious knowledge gap. When you say that these vehicles are not designed for towing, and I am referring specifically to Euro SUVs here, they were most definitely designed for towing. The designers typically gave them 7700 lb tow ratings for the mid size SUVs, tested to the TUV standards, which were out at least a decade before the SAE tow test standards were agreed. They typically offered those tow ratings without any requirement for powertrain or cooling system mods, it was standard equipment. Not like in North America, where vehicles typically have to include optional equipment to be able to tow at rated loads. The Euro manufacturers also included Electronic Trailer Stability Control features (developed by Continental and others), back around the year 2000. They offered rear camera features to include shifting the camera to show the tow ball for ease of hitching. On some models, they offered electric hide away hitches as factory options, in other cases they offered fixed or detachable swan neck hitches, which are the Euro standard. Of course the vehicles were designed for towing. Those who don't acknowledge that are either lacking information, or willfully ignoring it.

What the local marketing organizations for these manufacturers (not the engineers) vehicles decided was not to offer North American style receiver hitches at those ratings; not to offer the clip on tow mirrors they sold in other markets; and to ignore the electric trailer braking requirements in North America, requiring purchasers to rely on third party solutions.

I am not clear that it is a good idea to rely on local RV dealers for support when travelling, at least in regards to hitching and setup. There are too many incidents recounted here where an RV dealer didn't know how to set up a WD hitch correctly (I am sure some do know). For support, I assume you aren't referring to the tow vehicle dealer network, since there is almost universal agreement here that NA car and truck dealers know very little about towing, often not even how to read their own spec sheets. The best solution is for people towing is to educate themselves, IMO, so as to be more self reliant. That is my own approach on how to roll. As Bob likes to say, TETO.

[gypsydad]

Originally Posted by jcl

No, I don't think I am smarter than everyone. There are obviously some knowledge gaps among posters though, so I am simply providing information.

Firstly, what you refer to as modifying a vehicle, I refer to as installing a custom receiver hitch. And installing clip on towing mirrors.

The whole thread has addressed the issue of whether tow ratings are maximized in all markets, or reduced in some markets such as North America. No need to rehash that. No need to exceed load ratings for tires and axles. Our previous generation X3, built on a 3 series platform, had more carrying capacity, by hundreds of pounds, than a friend's RAM 1500. It also had more hp, better brakes, less rear overhang, and better handling. It was only offered with a 3500 lb hitch by the manufacturer, but aftermarket hitches can quickly resolve that issue.

Here is an obvious knowledge gap. When you say that these vehicles are not designed for towing, and I am referring specifically to Euro SUVs here, they were most definitely designed for towing. The designers typically gave them 7700 lb tow ratings for the mid size SUVs, tested to the TUV standards, which were out at least a decade before the SAE tow test standards were agreed. They typically offered those tow ratings without any requirement for powertrain or cooling system mods, it was standard equipment. Not like in North America, where vehicles typically have to include optional equipment to be able to tow at rated loads. The Euro manufacturers also included Electronic Trailer Stability Control features (developed by Continental and others), back around the year 2000. They offered rear camera features to include shifting the camera to show the tow ball for ease of hitching. On some models, they offered electric hide away hitches as factory options, in other cases they offered fixed or detachable swan neck hitches, which are the Euro standard. Of course the vehicles were designed for towing. Those who don't acknowledge that are either lacking information, or willfully ignoring it.

What the local marketing organizations for these manufacturers (not the engineers) vehicles decided was not to offer North American style receiver hitches at those ratings; not to offer the clip on tow mirrors they sold in other markets; and to ignore the electric trailer braking requirements in North America, requiring purchasers to rely on third party solutions.

I am not clear that it is a good idea to rely on local RV dealers for support when travelling, at least in regards to hitching and setup. There are too many incidents recounted here where an RV dealer didn't know how to set up a WD hitch correctly (I am sure some do know). For support, I assume you aren't referring to the tow vehicle dealer network, since there is almost universal agreement here that NA car and truck dealers know very little about towing, often not even how to read their own spec sheets. The best solution is for people towing is to educate themselves, IMO, so as to be more self reliant. That is my own approach on how to roll. As Bob likes to say, TETO.

I am not an expert modifying European SUVs, nor do I want to be. I am comfortable going with the experts who build their tow vehicles with towing in mind. But, here is the published ratings on a new X3, which to me would make it questionable for towing anything but light weight trailers, no matter which hitch you beef up and install after market. IMHO, of course!

Engine 2.0L I-4 248 HP 258.0 ft.lbs. @ 1,450 rpm
Transmission 8-spd sequential shift control auto w/OD
Gross Vehicle Weight Rating 5,137 lbs.
Curb Weight 3,931 lbs.
Front Gross Axle Weight Rating 2,403 lbs.
Rear Gross Axle Weight Rating 3,009 lbs.
Payload 893 lbs.
Max Trailer Weight 4,400 lbs.

Maybe I am missing something, or not as "trusting" to modify a vehicle such as this to tow a 23' or larger AS, vs a TV designed with the task of towing in mind, including HD towing hitch, HD cooling, transmission, suspension, and brakes to accommodate the intended use including towing a TT.

When someone is not trustworthy of or knowledgeable enough to understand
or research the MFG TV limits, (even when written in small print), who's fault is that: the MFG, the dealer, or the buyer? I always thought the buyer...but, hey, thats just me. No sense in overload on this topic...I see it all the time on the VW/Porsche/BMW threads here...never going to convince some folks. Be safe.

[jcl]

Originally Posted by gypsydad

I am not an expert modifying European SUVs, nor do I want to be. I am comfortable going with the experts who build their tow vehicles with towing in mind. But, here is the published ratings on a new X3, which to me would make it questionable for towing anything but light weight trailers, no matter which hitch you beef up and install after market. IMHO, of course!

Engine 2.0L I-4 248 HP 258.0 ft.lbs. @ 1,450 rpm
Transmission 8-spd sequential shift control auto w/OD
Gross Vehicle Weight Rating 5,137 lbs.
Curb Weight 3,931 lbs.
Front Gross Axle Weight Rating 2,403 lbs.
Rear Gross Axle Weight Rating 3,009 lbs.
Payload 893 lbs.
Max Trailer Weight 4,400 lbs.

Maybe I am missing something, or not as "trusting" to modify a vehicle such as this to tow a 23' or larger AS, vs a TV designed with the task of towing in mind, including HD towing hitch, HD cooling, transmission, suspension, and brakes to accommodate the intended use including towing a TT.

When someone is not trustworthy of or knowledgeable enough to understand
or research the MFG TV limits, (even when written in small print), who's fault is that: the MFG, the dealer, or the buyer? I always thought the buyer...but, hey, thats just me. No sense in overload on this topic...I see it all the time on the VW/Porsche/BMW threads here...never going to convince some folks. Be safe.

I am not an expert on the latest models. Our X3 was a previous generation, not turbocharged, more hp, more payload capacity, with a 3500 lb hitch available post-purchase from the BMW parts department, and a higher tow rating in Europe.

The X models (and many others) get larger/heavier/more hp with each successive generation. Our X3 had the same physical dimensions, and 40 more hp, than our earlier E53 X5, which suggests that given how similar the vehicles were, the tow ratings should be comparable. That X5 was rated at 7700 lbs by the manufacturer, and offered with a 6000 lb receiver hitch in North America.

The biggest reason I wouldn't tow much over 5000 lbs with our X3 was that the X3 wasn't wide enough for wider trailers. 5000 lbs wasn't a concern if set up properly. I know that some would tow an AS27 with it, but I wouldn't have.

Not sure if the specs you list above are for the Euro model, or the NA model. I don't see tow ratings on the BMW CA site, and the payload numbers are higher here than you list.

The current X3 is rated 4400 lbs tow rating in Europe. The configurator includes a factory hitch, and mentions trailer stability control, camera functionality for hitching, etc. I suggest it was very much designed to tow. The North American configurator I ran for the current X3 does not list towing specs, and does not offer a hitch. That may lead some to claim that it wasn't designed to tow. Of course, if I switch to the X5, I can get a hitch installed from the factory. I don't know their reasons for that. Perhaps it has to do with the profitability by model. If I wanted to tow with a current model X3, I would be quite comfortable purchasing an aftermarket hitch, and towing up to the 4400 lbs listed for the vehicle in other markets that trust purchasers to tow. I don't that that specific vehicle well enough to know if I would be comfortable much over 4400 lbs, partly due to the 4 cylinder turbo, so reserve judgement.

If we look at the mid size X5, which is commonly recommended for towing, I would be comfortable going up to an AS27, which is within the ratings from the design team, but not necessarily those published by BMW NA who market it here.

Cheers

Jeff

[Mattedfred]

Hey Jeff,

I'm following your logic and very much appreciate you taking the time to share it with us. Please keep doing so or shoot me a PM anytime for further discussion.

Safe travels!

Ted

[Countryboy59]

Originally Posted by gypsydad

From post #387: "With respect to manufacturer's tow ratings, I too am a skeptic. I think that they are not particularly valuable. Sometimes they are too low (when a manufacturer doesn't care about a high tow rating) and often they are far too high (see recent pickup truck ratings). The SAE tow test standard is often quoted as something that makes these ratings more real, but I would be more confident if the SAE standard considered more factors than it does. I think the main thing it does at the moment, in combination with the exploitation of it by pickup manufacturers, is give some vehicle purchasers, particularly those new to towing, a false sense of security." ??

Lets see...do you have a false sense of security purchasing a TV with decent payload, power, braking, transmission, suspension, and cooling system set up for HD towing by the MFG? Or do you have a false sense of security taking a passenger vehicle, not designed as a TV, to someone and have him "modify" by adding a trailer hitch for an AS taking limits beyond the MFG specs (no modification to brakes, cooling, transmission, suspension) for said vehicle....Hmmmm? Do you feel lucky or what!

A competent person can modify a vehicle safely. Hot rodders and customizes have been doing it for years. The average person these days, with google skills but nothing else, may want to leave things alone. Mechanical aptitude ain’t what it used to be.

[Countryboy59]

Originally Posted by dznf0g

If that is your preference, go for it. There is nothing wrong with an over-spec'd" truck for the job. BUT, that does not mean that if someone specs a truck exactly for the job, that the fear of God should be placed upon them. (as many posts here over the years have stated.

Also true. But people aren’t as in touch with the road as they used to be. They don’t learn to drive. Evidence the numerous people who drive down the entrance ramp, turn signal blazing away, and run right into the side of the only other vehicle on the road at 2 am. I had this almost happen while towing my Airstream in the right lane of the freeway. The person panicked and took the shoulder, the passed me a few miles later with his wife wagging her finger at me.

Today’s drivers need all the help they can get.

[richard5933]

Originally Posted by Countryboy59

A competent person can modify a vehicle safely. Hot rodders and customizes have been doing it for years. The average person these days, with google skills but nothing else, may want to leave things alone. Mechanical aptitude ain’t what it used to be.

The mechanical skills most people have nowadays aren't what they used to be, but neither are the vehicles. We're not talking about modifying a vintage car here with a run-of-the mill steel chassis. We're talking about some really high-tech chassis which have all kinds of odd quirks such as built-in crumple zones and weight-reduction going on, as well as the use of some pretty unique alloys and components.

Someone may be expert in how to build and weld on a hitch, but unless they know enough about the design of the frame they're about to weld it to, it could be a disaster in the making. I think I'd want someone beyond 'competent' and more towards 'expert' in the particulars of the make/model at hand.

[propchef]

Originally Posted by jcl

I am not an expert on the latest models. Our X3 was a previous generation, not turbocharged, more hp, more payload capacity, with a 3500 lb hitch available post-purchase from the BMW parts department, and a higher tow rating in Europe.

The X models (and many others) get larger/heavier/more hp with each successive generation. Our X3 had the same physical dimensions, and 40 more hp, than our earlier E53 X5, which suggests that given how similar the vehicles were, the tow ratings should be comparable. That X5 was rated at 7700 lbs by the manufacturer, and offered with a 6000 lb receiver hitch in North America.

The biggest reason I wouldn't tow much over 5000 lbs with our X3 was that the X3 wasn't wide enough for wider trailers. 5000 lbs wasn't a concern if set up properly. I know that some would tow an AS27 with it, but I wouldn't have.

Not sure if the specs you list above are for the Euro model, or the NA model. I don't see tow ratings on the BMW CA site, and the payload numbers are higher here than you list.

The current X3 is rated 4400 lbs tow rating in Europe. The configurator includes a factory hitch, and mentions trailer stability control, camera functionality for hitching, etc. I suggest it was very much designed to tow. The North American configurator I ran for the current X3 does not list towing specs, and does not offer a hitch. That may lead some to claim that it wasn't designed to tow. Of course, if I switch to the X5, I can get a hitch installed from the factory. I don't know their reasons for that. Perhaps it has to do with the profitability by model. If I wanted to tow with a current model X3, I would be quite comfortable purchasing an aftermarket hitch, and towing up to the 4400 lbs listed for the vehicle in other markets that trust purchasers to tow. I don't that that specific vehicle well enough to know if I would be comfortable much over 4400 lbs, partly due to the 4 cylinder turbo, so reserve judgement.

If we look at the mid size X5, which is commonly recommended for towing, I would be comfortable going up to an AS27, which is within the ratings from the design team, but not necessarily those published by BMW NA who market it here.

Cheers

Jeff

Currently, the tow package is not available for the X5, not sure about the X3. This, according to BMWNA, is due to the parts shortages. Other options eliminated are the head's up display, upgraded hifi, and the touch screen. There currently insnt a good aftermarket solution for the G05 for hitches.

The X3 is available in a number of trims, including the M-Sport which is a turbocharged inline 6, not a 4. At 500+ HP it supplies some serious grunt.

[Glenritas]

See next post for the complete post , missed the top when dragging and dropping ... disregard the below and read it in the next post .









In the US trailers are designed with a bare minimum of 10% Tongue weight but most are 20% or more .
The load is forward of the axels and more weight is on the tongue . Think Airstreams 900 - 1200# .

Trailers are also much larger and heaver and keep getting larger and heaver !

So there is a real good reason the the EU Mfg’s don’t allow the same vehicle to tow in the US !

Ahh … BUT there is a company that can make it possible to hook up a US Trailer to that European vehicle with a custom made (MAGIC) hitch set up that will make a low center of gravity , independent suspension great handling vehicle (that is way under spec’d) to haul the US trailer (Airstream) of any size or weight .

The Mfg’s obviously have no clue about what their vehicles can tow or not tow ! Because a small company in Canada has made it posable to go where no Mfg is willing to go …. Beyond physics .

Stick with the Mfg’s specs !


Definition
physics : plural noun

The branch of science concerned with the nature and properties of matter and biology , includes mechanics , heat , light and other radiation , sound , electricity , magnetism , and structure of atoms .

the physical properties and phenomena of something : the physics of plasmas .

[Glenritas]

So one thinks because in Europe you can tow with a car or suv up to 7700# then your logic is that the same can be done in the US .

But the MFG allows it in Europe for the same vehicle but not in the US , why not ?

Because in Europe Tow trailers are set up with the load centered over the axles and very low tongue weight like 3% so cars just pull and not support the load also the hitches can only carry 250# .

Towing speed in Europe is 45 MPH !

In the US it’s 55 to 75 ! And we all know that people will push that up at least 10 MPH !
In the US trailers are designed with a bare minimum of 10% Tongue weight but most are 20% or more .
The load is forward of the axels and more weight is on the tongue . Think Airstreams 900 - 1200# .

Trailers are also much larger and heaver and keep getting larger and heaver !

So there is a real good reason the the EU Mfg’s don’t allow the same vehicle to tow in the US !

Ahh … BUT there is a company that can make it possible to hook up a US Trailer to that European vehicle with a custom made (MAGIC) hitch set up that will make a low center of gravity , independent suspension great handling vehicle (that is way under spec’d) to haul the US trailer (Airstream) of any size or weight .

The Mfg’s obviously have no clue about what their vehicles can tow or not tow ! Because a small company in Canada has made it posable to go where no Mfg is willing to go …. Beyond physics .

Stick with the Mfg’s specs !


Definition
physics : plural noun

The branch of science concerned with the nature and properties of matter and biology , includes mechanics , heat , light and other radiation , sound , electricity , magnetism , and structure of atoms .

the physical properties and phenomena of something : the physics of plasmas .

[RMNummi]

Just when you wanted to note that there are only two sides to this discussion, those that think the tow rating is a suggestion and those that think it’s the holy writ. As a practitioner of the dark legal arts, here’s my take: It doesn’t really matter.

What matters is your blown TV warranty. Your coverage rejection when in an accident, your AAA Platinum or Good Sam “tow” coverage rejection (yep, read the fine print)… your house being repo’d by the insurance co. The free ticket out of liability that you delivered to the other driver(s) when they check your trailer weight vs the rated vehicle capacity.

Whether your a believer in tow ratings or not….screw up once, they will take your house, your bank account and anything else you have that can be monetized. Lawyers are the bane of our existence… they reduce max ratings for no other reason than it’s a “safety margin”…. (Read: We won’t have to pay)…

Like I said, the argument of can they, should they etc. is irrelevant. It’s so you want to gamble with your family’s well being.

[jcl]

Originally Posted by Glenritas

So one thinks because in Europe you can tow with a car or suv up to 7700# then your logic is that the same can be done in the US .

But the MFG allows it in Europe for the same vehicle but not in the US , why not ?

Because in Europe Tow trailers are set up with the load centered over the axles and very low tongue weight like 3% so cars just pull and not support the load also the hitches can only carry 250# .

Towing speed in Europe is 45 MPH !

In the US it’s 55 to 75 ! And we all know that people will push that up at least 10 MPH !
In the US trailers are designed with a bare minimum of 10% Tongue weight but most are 20% or more .
The load is forward of the axels and more weight is on the tongue . Think Airstreams 900 - 1200# .

Trailers are also much larger and heaver and keep getting larger and heaver !

So there is a real good reason the the EU Mfg’s don’t allow the same vehicle to tow in the US !

Ahh … BUT there is a company that can make it possible to hook up a US Trailer to that European vehicle with a custom made (MAGIC) hitch set up that will make a low center of gravity, independent suspension great handling vehicle (that is way under spec’d) to haul the US trailer (Airstream) of any size or weight .

The Mfg’s obviously have no clue about what their vehicles can tow or not tow! Because a small company in Canada has made it posable to go where no Mfg is willing to go …. Beyond physics .

Stick with the Mfg’s specs !

I don't think that any Euro vehicle rated to tow 7700 lbs should necessarily be set up to tow that weight in North America, but let's look at your points one by one. There is a significant amount of misinformation in them.

It is in fact the tow vehicle manufacturer, who has the design and testing engineers on staff, who typically sets the higher towing limit. The lower tow rating limits under discussion are set by the marketing department of the manufacturer, regional distribution companies, for whatever reason they so decide. There may be good reasons for it in some cases. One example is if the US marketing arm of a Euro manufacturer only offers a lower rated hitch (they need to source 2" receiver hitches locally, since the factory engineers don't acknowledge them), then one shouldn't necessarily put a heavier trailer behind that light duty hitch. Better to buy a stronger, more robust receiver, than can handle WD equipment. We just can't necessarily get it from the accessory department of the manufacturer.

I don't think many trailers are set up with 3% tongue weight, but 4-8% is common. I would use 5% for comparison purposes, compared to 10% in North America. That is the same as many boat trailers in North America. It is travel trailers that commonly have the high tongue weights you reference, especially the larger ones with more creature comforts. Not all types of trailers have the same towing characteristics. A boat on a trailer carries the weight very low. The weight is concentrated close to the trailer axles, especially the engines, batteries, outdrive, and keel. Pretty much like that Euro travel trailer you describe. But recall also that when the Euro manufacturer publishes a tow rating, they don't specify the trailer characteristics. They assume you will tow any type of trailer.

Towing speed limits in Europe may be 45 mph in some places (it is 30 within city centres), but that certainly isn't the standard. Unless specified otherwise, it is 80 kph, equal to 50 mph. If you want to tow faster than than, you need to have your trailer inspected, and if you meet the technical requirements you can get a sticker that permits towing at 100 kph, or 62 mph. An example of the technical requirement is that they check for the presence of trailer shock absorbers, which are not commonly used. Recall also that they are publishing these towing weights without the benefit of electric trailer brakes, or any WD equipment.

One of the usual limitations of a Euro vehicle for towing is rear axle loading due to tongue weight. That is why they use low tongue weights. We have a technical solution for that in North America, one that respects physics, and known as a weight distributing hitch. They don't allow them. Using WD doesn't allow one to exceed safe and rated rear axle loads, but it allows one to use more tongue weight, while respecting the axle rating. No magic required, just physics.

One of the reasons for referencing Euro manufacturers not only allowing, but advertising and promoting, higher tow ratings, is that in this thread, we keep hearing about "but the engine/transmission/cooling system/brakes/etc" aren't designed for that higher weight. We see predictions of catastrophic tow vehicle powertrain failures. The vehicle is usually fully capable of comfortably towing the trailers under discussion, from the standpoint of the powertrain. What is required is figuring out how to use WD equipment, something that all NA manufacturers recommend for things like pickups, but in this case on a vehicle that wasn't tested with WD equipment, likely because it isn't legal where the engineers live and work. But there are North American towing experts who know how to design, build, and mount a hitch suitable for WD equipment. No magic.

[jcl]

Originally Posted by Countryboy59

A competent person can modify a vehicle safely. Hot rodders and customizes have been doing it for years. The average person these days, with google skills but nothing else, may want to leave things alone. Mechanical aptitude ain’t what it used to be.

Agreed.

One alternative course of action, if one does not have the skill set or experience to modify a vehicle or receiver hitch, is to seek out a supplier who does have that experience. I would look for one with a long track record of similar work, and high customer satisfaction ratings.

[Glenritas]

jlc
This being an Airstream forum , the discussion is focused on towing an Airstream and tow ratings for Tow vehicles.

Comparing Euro and NA tow ratings is mute as we are in NA .
My point is trailer design and type is relevant.
So if one is towing an Airstream in NA then one should tow within the Mfg’s spec .

[gypsydad]

Post #414 mentions a major reason not to modify outside MFG specifications, but some folks here don't think of this, I fear. I know from actual accident with insurance claim experience; this concern is a big reason to stay within MFG limits on payload and towing, without modifications to your vehicle.

But take it back a step or two...what I see here is "some" don't know enough about how the limits are set nor tested by the MFG? You really think a MFG would knowingly list the limits for towing with their vehicles if they could not hold up by consumers? (The lawyers would love to have a case or two like this!)

When I talked with MBZ last year in Austin about my son's GLE450 4Matic which was equipped for towing his newly acquired Basecamp 20X, they told me it had the tow package from MBZ. We went over the numbers and he was below max payload and towing limits for that AS. I asked about my GLE 350 4Matic that we own, and he said if it could be set up with a MBZ hitch and add a brake, but it would not be covered by warranty if something were to happen, and cautioned against. I am sure Andy or someone else here would argue that it would be fine, and that it could be modified to tow a 23' AS? I surely would not go that route. Do you think Andy would come to the US to argue in court should I have an accident? Don't think so...

So sure, we all understand you can get just about anything done you want in modifying a vehicle today. But I stand by earlier comments; modifying the vehicle by adding a beefed up tow hitch, and not taking into account the other factors of handling/controlling a heavy trailer is crazy. Should something happen going down a mountain at highway speed with a heavy trailer in tow with a short wheelbase vehicle, stock brakes/suspension...I don't care how well it handled as a "road car" by itself, your not going to convince me to risk my family. Nor can you demonstrate a thorough mathematical engineering and stress analysis has been done on the modifications, from what I am reading? If not, specs are meaningless...therefore there likely are no tow limits, payload concerns, nor axle load concerns to worry about, if and when you modify!

[jcl]

Originally Posted by Glenritas

jlc
This being an Airstream forum , the discussion is focused on towing an Airstream and tow ratings for Tow vehicles.

Comparing Euro and NA tow ratings is moot as we are in NA .
My point is trailer design and type is relevant.
So if one is towing an Airstream in NA then one should tow within the Mfg’s spec .

The question you asked above was:

But the MFG allows it in Europe for the same vehicle but not in the US, why not ?

What should we do if the manufacturer's towing specs don't cover a North American model Airstream? A trailer that is designed to use WD? One that has a heavier tongue weight, and so benefits from WD equipment?

Could we consider the European towing spec, and identify what is different here? That is what the discussion is about.

The answer IMO is the recommended use of WD equipment, and the legal requirement for electric trailer brakes over a certain trailer weight.

It isn't the trailer design (which is not specified in the tow rating); the travel speed (which is comparable); the grades (which are steeper in Europe); and so on. Those are all diverting from the two key reasons noted above.

[Glenritas]

Do not substitute Europium tow spec’s on this continent !

Trailer design IS different there then here ! It makes a big difference in dynamics of the “rig” .

If you want to tow a new Airstream in Europe, Airstream has a special EU model that is shipped over there to be outfitted there by other companies .
If you want to ship a vintage Airstream there it has to be modified to EU spec .

I hope that clarifies that for you .

Now about tow ratings EU spec’s don’t fly in NA ! Only NA spec’s matter here !
For legal , insurance , warranty , safety and liability reasons !

Now jcl you go ahead and and ignore the NA spec’s and suffer the consequences.

But please don’t encourage others to ignore them !

After all this thread could be used against you in court if someone who is involved in accident because you encouraged via this thread and they named you as the source of their decision to ignore the spec’s . In this world it could happen .