RJFabCab

The factory tow package has a capacity of 7700 lbs with a maximum tongue weight of 616 lbs.

It doesn't matter whether a weight distributing hitch is used or not... the limits remain the same.

Why is that? Perhaps the Cayenne frame/tranny are mighty strong but the relatively short wheel base is the limiting issue?

How does Porsche, or any other manufacturer for that matter, determine the max. towing limits? I'm guessing that they look at stress on the frame, wheel base, tow vehicle weight, and stability but I wonder how they come up with these limits.

Here's why I ask. With the 'ole 10-15% of your load on the tongue rule, I would have a tongue weight of at least 700 lbs with a 7000 lb load which already exceeds the Cayenne's tongue weight limit.

So, what's 'better'?

1. Tow 7000 lbs with a tongue weight of, say, 550 lbs
2. Tow 7000 lbs with a tongue weight of 700 lbs
3. Don't tow more than 6000 lbs and keep the tongue weight at 600 lbs

ltc

IIRC, it is stated to NOT use a load distributing hitch with a Cayenne.
I don't remember if that was specific to PASM equipped vehicles or not.

The 'rule of thumb' is somewhat irrelevant; the governing specification/document is the manufacturer published/supplied capacities (at least from a legal perspective).

So, the answer is #3.....or more specifically IMHO , just buy a proper tow vehicle, like a Ford Superduty and never have to worry about such things.

RJFabCab

Lewis, how the heck are ya?

Porsche does not recommend the use of a WD hitch... that's about all the manual says LOL.

I contacted 3 dealer service departments (stop laughing and spitting up your brew!) regarding the WD hitch and they all said that a WD hitch is fine, but it is NOT to be used with the PASM due to the suspension auto-leveling characteristics.

That being said, my Cayenne S is non-PASM and I've been running the Reese/Draw-tite Pro Series WD system with integrated sway control without issue. The CS actually towed quite well before the WD install, but now it is much more stable over uneven transitions at speed with improved steering.

I'm gaining experience, but I'm still a towing newb. If the rule of thumb is somewhat irrelevant, then should I attempt to tow with the heaviest tongue weight possible (less than 616 lbs, of course) regardless of the weight I'm towing?

Some folks have told me that "you can never have too much tongue weight" as long as I stay within the max. limits.

I'm just trying to figure out what's best when towing a load of about 6000-6500 lbs.

Unfortunately, something like the Superduty Beast is out of the question since the vehicle must be dual purpose... it's the primary ride for my wife and kiddos!

ltc

Are you using one of these to measure tongue weight?
http://www.sherline.com/lm.htm
http://www.sherline.com/lmbook1.pdf

Have you read this?
http://www.sherline.com/lmbook.htm

Here is a quick worksheet:
http://www.sherline.com/lmwkshet.htm

RJFabCab

I have a Sherline scale and am familiar with all the material you linked.

If 10-15% of the loaded trailer weight should be on the tongue, then what good is a factory tow package with a 7700 lb capacity on a hitch with a max. tongue weight rating of only 616 lbs?

I guess I already know the answer to that since I'm referencing a company that has hidden wiring harnesses and 'unspecified' load ranges for trailer lights.... !!!!!!!!!!!!!........!

I suppose higher tongue weights lead to increased stability in crosswinds and other various conditions.

With respect to the Cayenne's numbers and the 9-15% rule, would it be unreasonable to tow 6500 lbs with a 550 lb tongue weight?

If the 9-15% rule is so important (per Sherline for tandem axles), why would Porsche list the 7700/616 limits?

ltc

What, are you questioning all those years of towing experience that Porsche has?


Actually, if you dare go WAY back into the archives, the towing capacity and tongue weight specifications have "evolved".....they started becoming somewhat more bizarre after the "Touareg and the jack knifed boat towing" lawsuit, shortly after both vehicles were introduced.

No, don't ask why someone would actually go and research stuff like this (lawyers may be watching).....

RJFabCab

Touareg suit, eh? I'll have to do a little investigating. RE Porsche's vast towing history...

henna gaijin

My '05 Touareg V8 hitch has a sticker which states 7700 lb capacity with a max tongue weight of 770 lbs.

Why would the Touareg be different?

Edit to add picture of receiver label:

ltc

Again, if you go back into the alpha/beta archives, you will find that the capacities have 'evolved' over time, with no explanation forthcoming from PAG.

It is also interesting to note the differences when it comes to the use of various hitch types (weight distributing vs non), as evidenced on your Touareg label.

The towing hardware (and even the software !!!!) is OEM to VAG and PAG (I know, VAG, PAG what's the difference anymore) by Westfalia.

The individual labels/capacities are the responsibilities of the individual car companies.

Now, without going down an inevitable rat hole (re: numerous discussions in the racing/DE forum, where there is quite a bit of towing experience), just because a label says you CAN tow a certain amount, it by no means says you should.
Wheelbase matters (and the Cayenne/Touareg is sort of short) as does staying well below max ratings, as does what type of trailer you are towing.
This will become apparent, right before you, your Cayenne/Touareg and trailer flip over when things go horribly wrong (crosswinds, tailwagging, emergency braking/lane change, etc)

RJFabCab

No difference in limits with WD vs WB... just about every other hitch I've looked at has increased limits for a weight distributing system. That's why I'm guessing that stability is the limiting issue here, not hitch, tranny, or chassis strength.


Safety is my number one priority, and thoughts about safety are what got me started on this thread. I hope to never see the 'limits' you describe above.

Here's my load: 2800# aluminum V-nosed trailer, 3200# car, 200# wheels/tires. That's about it... rougly 6200# with a WD anti-sway hitch.

So, with respect to the Cayenne, what tongue weight should I aim for?

500#? (for buffer under the 616# limit)
600#? (near the 616# liimit, but closer to the 10% on the tongue rule)

No, I don't have enough room for a Superduty!!!

ltc

Agreed.
We'll try and figure out the WD vs PASM another day.

FWIW and IMHO, with the non-PASM/WD hitch, I would go for the 10% tongue weight. Assuming double axle trailer, some people actually say as low as 9%.

Pay careful attention to cross wind buffeting and any tail wag, especially with a longer trailer (you didn't specify trailer length). Make sure you can reach your trailer brake control unit in case you have to manually stop a tail wag.
Also try and come up with some sort of sideview mirror extentions for towing. Toby posted some, albeit somewhat lacking in the design department, which would safely do the job.

That's OK, neither do I. I just 'borrow' the bride's Excursion diesel

As 'skl' can testify to, towing an aluminum enclosed car hauler with a Cayenne can be done ("!" and sideview mirror issues aside for the moment), but once you tow the same load with a proper tow vehicle, the differences become apparent, especially in stability/visibility and comfort.

RJFabCab

The trailer's a 20' Featherlite with rearward positioned dual axles, which I think works out nicely with a rear engined car and the Cayenne's wimpy tongue weight rating. As you mention, Sherline states a low tongue weight of 9% for tandem axle trailers. That's a Featherlite file foto... that trailer looks a tad long!

The stock mirrors are useless for visibility, so I'm using some aftermarket units (pictured) with one mod... I bought some bungee cords to wrap aroud the frames to stabilize the units and it works great.

I haven't experienced any significant sway or tail wagging yet... knock wood. I did plan for this, however, when mounting the brake controller. It's under the dash above my right knee within easy reach.

Thanks for the tippers.

ltc

You should be good to go.

maverick1715

Hello everybody.

I'm new to this forum and to the trailer world. First things first I want to thank the whole community for providing all these extremely valuable information. The truth is that many car salesmen most of the times have no idea about some technical data and specifications of the cars they sell. I landed onto this forum after lots of research about maximum tongue weight about my Porsche Cayenne. I found the following information and I thought it might be a good idea to share it.

First of all, the 2012 Cayenne Turbo manual doesn't mention anything and anywhere about not allowing the use of weight distribution system with the air suspension configuration. More specifically, I own the 2012 Turbo model and this is the info I wanted to share with everybody:

http://buyersguide.caranddriver.com/...e/specs/336458

http://newportautocenter.com/Newport...WD-4dr/357710/ click on the specs tab

http://www.porscheofsilverspring.com...tion-v1596844/ click on the specs tab

http://www.penskeautomall.com/detail...-11884443.html click on the spec tab

I found dozens of reputable web sites with exactly the same numbers. They all state 4 different weight numbers for the Porsche Cayenne:

1. Dead Weight Hitch - Max Trailer Wt. 5000 lbs,
2. Dead Weight Hitch - Max Tongue Wt. 500 lbs
3. Wt Distributing Hitch - Max Trailer Wt. 7716 lbs
4. Wt Distributing Hitch - Max Tongue Wt. 1157 lbs

The hitch receiver sticker on my Cayenne (stock receiver) states Max tongue weight with OR without weight distribution system 616lbs. The manual of the Cayenne doesn't state anything about "Weight Distribution System" except max tongue weight, which of course is 616lbs. why? Maybe because in Europe they don’t even know the phrase “Weight distribution? Maybe because of liability? Maybe because they made a mistake as many folks mentioned on previous threads? After all the research I made and after the above presented evidence, this is the conclusion I came into: Weight distribution systems transfer part of the tongue weight on the front axles of the TV and some on the TT. With that being said, after proper Weight Distribution configuration and the correct spring tension, people can exceed the 616lbs on the tongue up to 1157lbs. Is it wise to do? Probably it's not wise to go as close as to the absolutely maximum tongue weight, which is 1157lbs. But can we use a trailer which tongue weight is around 900lbs without any hitch reinforcement and only by using a high quality distribution system and swing control? I would say yes. Many people are oppose of an SUV such as Touareg or Cayenne used as towing vehicles, maybe because of their short wheel base; With respect to them, I believe that these 2 vehicles are extremely capable of towing if they are on the right configuration and of course with the right driver. I'd love to hear your comments and many thanks to everybody for taking the time on explaining and sharing your experiences.

forbin42

You can go by what these other websites say or you can go by your manual. Guess which one will prevail when you have warranty work done.

The weights listed in the manual and on your hitch are calculated by the vehicles rating and configuration. The hitch tongue capacity is the balance of cargo capacity left after rated gross weight (passengers, cargo, fluids, etc.) It takes into account the vehicles rated suspension, brakes, and what everyone here forgot about... wheels and tires. Porsche recommended tires are designed for highway passenger use, not heavy duty towing, hence the low tongue weight. If you go and calculate front and rear axel weight, curb weight, cargo, passengers, etc., and max out the tongue weight, I come within 8 pounds of my tires max load rating. While a WD hitch may move some of that weight forward, you need to take in to account your passenger and cargo and come up with max weight distro for your trailer. That said, the 9-15% rules depends on the trailer, configuration, shape, number of axles, etc. No one here is really going to be able to tell you. Load it up and take it for a spin on a safe road and see how it handles. Sway bars are going to allow you to cheat. Frankly, they are for folks that feel uncomfortable towing a trailer when the semi blows by.

Same goes for the Ford and Chevy SuperDuties. Goi spec them out. Based on long bed, short bed, Avalanche, etc., the max load rating changes because the weight of the vehicle changes which adds or subtracts cargo load maximums. Picking different wheels and tire configurations will also change the vehicles ratings. It is my the poster above noted the Tourag can tow more. Fewer options, different wheels and tires.