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So the Macan towing capacity is 4400 lbs max, vs 7700 lbs max for the Cayenne.

Why such a big difference?

It can't be the engine or brakes, because some Macan models have at least as much, if not more, engine and braking capacity than some Cayenne models

What would it take for Porsche to significantly increase the towing capacity for the Macan?
Wheelbase and tow vehicle weight probably affect the complex industry standards (SAE, DIN, etc) used to determine the rating. Unibody strength and receiver attachment joints probably come into play too. It’s complicated stuff. I’ve read the Cayenne 8-speed transmission with torque converter replaced the original dual clutch tranny specifically to optimize towing performance. Horses for courses.
 
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Tongue weight recommendations and limits vary a lot between the U.S. and Europe for reasons that are fuzzy. I’m not sure about Oz. Europeans seem to run much lower tongue weights as a percentage of towed weight, about 6-8% IIRC, while U.S. recommendations are generally 10-15%.

VWAG straddles the two standards, using stickers on hitches for American vehicles that state tongue weight limits of either 8% or 10% of max towed weight. My Cayenne has a 616 lb limit for 7700 lb towing capacity (8%) and I’ve juggled loads fore/aft of trailer axles to live with that because I towed no more than 6000 lb. But in some cases VW sent Touareg owners new stickers with a 770 lb (10%) limit.

One of the best resources for towing is the Airstream Forum. It includes a 75-page thread dedicated to towing with the Cayenne-Q7-Touareg platform, which includes generally helpful advice as well as discussions of the international standard discrepancies described above. The consensus on that thread seemed to be that slower towing speeds in Europe don’t require the higher tongue weights commonly used in America, but I never saw documentation of that. Are towing speeds really lower in Europe? Weight Distributing hitches are common in America but not in Europe, adding to the confusion. Good luck!
 
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It appears they’re using the 10% rating. It remains unclear whether this is for towing performance (sway control) vs structural reasons, so it’s best to assume it’s a firm structural limit. CanAm RV in London, Ontario, Canada seems to be a leader and resource for German SUV towing in North America. They do hitch reinforcement work and are trusted by the Airstream community. They sometimes reply to email questions as well.

Keep in mind your tongue weight includes everything hanging off the receiver, including the shank and ball. It’s also wise to minimize cargo as much as possible. It’s better carried over the trailer axle than behind the back seat. The 440/4400 lb rating gives you loading options, especially if you’re not pushing the 4400 lb limit. Good luck.
 

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I’ll check out the video in the morning. As an engineer I’d appreciate a clear technical illustration. Here’s a folksy description someone posted on the Cayenne thread on the Airstream forum:

"Ron and I hitch up his trailer. The rear of the truck sits way low, the front is way high, and the front wheels don't steer or brake worth a darn 'cuz of this. We stick a long pry bar into the back end of his truck frame and pull up hard. The rear rises and the front drops. I have Ron trot along holding that bar up as I drive...the truck drives really well now, but Ron is getting tired. He chains the bar to the trailer tongue so he can take a breather. This works OK on the straights, but is a big problem on curves. We figure out a pivot system for the point the bar attaches to the truck. It turns well, but is really bumpy. Ron's Mrs. says to use spring steel bars. Duh!...Why didn't we think of that? Ron and I, and his Mrs., just invented the weight distributing hitch."

So lifting the rear of the load bars works just like Ron's pry bar. We were fortunate to have a very light but effective WDH. I wasn’t sure they were commonly used in Oz. The increase in stability is appreciable.
 

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Your video dives into the physics quantitatively. Mine was a tongue-in-cheek qualitative illustration. You have an excellent grasp of the concept. The Airstream forum covers the pros and cons of relying on PASM alone or disabling it with a WDH. It will help level things but won’t transfer load as much as a WDH. IIRC my setup transferred about 300 lb onto the front axle. The whole car settles in slightly lower if you carefully measure fender heights before and after. Be sure to get the proper load bars for your trailer weight. Stiffer ones will give a rough ride. They‘re designed to bend and flex.

I’ll see if I can dig up my data but we sold the camping trailer after one season. After a fun 2021 COVID era experiment, we learned a lot and know better what we’ll buy if we ever decide to re-enter, with either a towed teardrop trailer or a Class B van. This would be lighter, more aerodynamic, and better built/finished than what we had. Towable easily by a Macan too.
For use a couple times each year Airbnb, offers nice options in the U.S.. Some owners will even set their rig up on the campsite of your choice, with no towing required.
 

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OK @David L , you've shared the physics description of Weight Distributing Hitches (WDH) and I've shared the folksy description. Now I'll share a real example, maybe something with lasting value on this towing thread.

Online you'll find how to measure the WDH effects on each axle by doing three passes over a truck scale. In the U.S. we have "Cat Scales" at many truck stops. Your 1st pass is just your Tow Vehicle (TV) with driver, passenger(s), and a full tank of gas. The 2nd pass adds your trailer attached but the WDH load bars disconnected. The 3rd pass is with the bars in place.

Here's a pic of my Fastway e2 roundbar WDH, one of the lighter hitches available in the states.
Tire Automotive tail & brake light Wheel Vehicle registration plate Automotive tire

Note the back of the load bar rests on an L-bracket attached to the trailer A-frame. It slides across the bracket as you turn and the friction dampens sway effects. Never lube this interface btw! If you shift the bracket upward per the red arrow, you increase the torque on the WDH, shifting more weight forward. My trailer sales team set it up in a position that helped but didn't seem to level things like it should. I weighed the setup, which quantified the OK/wimpy effect. Then I unbolted the L-brackets and raised them about an inch to the next hole and repeated the weighing process. Here's a table with the results of both setups.
Font Line Material property Parallel Pattern

The effect is clearer when you see the front and rear fender heights graphically (below). The black line shows how the Cayenne rides higher in the rear in its unloaded state. This makes sense since adding the max passenger and cargo will more heavily affect the rear. It probably settles into a level position under full load. The red dashed line is with the trailer on the hitch but without the load bars in place. Then the blue line is with the load bars in place, using the dealer installed WDH setup. The green line is with the L-brackets raised one notch. Note how it's then perfectly level.
Rectangle Slope Font Parallel Screenshot

The table above shows that the bars removed 440 lb from the drive axle, put 300 of this on the front axle, and put the other 140 lb on the trailer axle. I've read btw that this shift doesn't change your permissible tongue weight (TW). It just improves stability and handling, as well as helping to keep you within your permissible rear axle load limit. I managed to keep TW under both the 620 lb (8%) limit and the 770 lb (10% limit) and TW was 11.5% of trailer weight. Handling was very noticeably improved with the bracket shift, feeling much more "planted", with none of that "floaty" steering feel and no sway issues even at 65 mph in crosswinds up to 25 mph.
 

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i was surprised by how well the weights agreed across the weighing passes, but that doesn’t mean they’re precise, just reproducible. The blue shaded cells are the raw axle weight data from the scales. You’re looking at the white cells with TV and trailer weights derived from the scale data. TV = sum of two axles. Trailer = tongue + axle. These are the changes when load bars were installed. Front; 2548 to 2840 (+300). Rear: 3480 to 3040 (-440). Trailer: 4640 to 4780 (+140).

You’ve probably noticed the incredible range of teardrop concepts out there. There’s a lot of creative design in that space. Larger trailers tend to be copies of competitor’s floor plans using the same components with tweaks inmaterials and features. Build quality is sketchy by automotive standards. Teardrops are simpler with more rugged build. Some are very clever, like Swiss Army knives. While the Cayenne will tow larger trailers, they’re overkill for our lifestyle. Like you, I‘d rather keep trailer weight less than 2/3 of TV weight, regardless of towing ratings.
 

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Trailer weight = combined weight - tow vehicle weight
Trailer weight = 10,660 - 5420 = 5240

Then, Tongue weight = trailer weight - trailer axle load
Tongue weight = 5240 - 4640 = 600

And tongue weight is determined without load bars in place. You can also buy a special tongue weight scale to directly measure it (unhitched) as you move your load fore and aft or change what you bring along, but this derived method is quite precise too. Just keep the shank and ball off for your first scale pass so their weight doesn't get included in the tow vehicle weight. You can extract a lot of information from those 3 passes over the scales.
 

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Well it's clear the drivetrain and suspension will handle it, but the base engine will probably need to work harder than the bigger engines in other trims.

Wind resistance is your biggest load factor and it increases exponentially with speed. Slower speeds are your friend for this and other reasons, especially on windy days. You don't want a "wag the dog" situation. And with that in mind, consider a weight distributing hitch (WDH). There's a lot posted on those in other threads.

We towed a roughly 6000 lb camper last year with a Cayenne S and learned a lot in the process. It doesn't have a dual clutch transmission, but with its transmission and torque converter, it's recommended to avoid using cruise control, as it will try to shift up into overdrive(s) then back down very frequently. Without cruise engaged, it doesn't do all of that "hunting" for a nonexistent (or briefly existent) perfect gear. This also keeps the rpms steady in a nice range. It might be good advice for the PDK too.
 

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I’m interested in this thread as well, and using base for a 320-S. hitch is going on in a few weeks, and looking for some kind of wireless (or no wire cutting) solution.
We had good luck with the Curt Echo wireless brake controller. It can be a bit fussy to pair with German SUV's but once paired it's solid. Just be sure your headlights are set to "off", not auto, when you plug it into your car. Then connect your trailer and switch to "on" for towing and it should work fine. If it ever loses its Bluetooth connection (very rare), it continues to operate with the same settings you've established. There are other good wireless options too.
 

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One more recollection on turbocharger boost. IIRC, our Cayenne required less boost in lower gears, often none. Apparently higher rpm requires less help? Without cruise it happily ran most of the time in 6th at 2200 rpm, shifting up to 7th on downhill grades and maybe briefly into 5th on steep uphills. With cruise engaged it would "hunt" more, trying to get up into 7th more often/briefly and sometimes even into 8th (both of which are overdrive gears). However, the boost would increase with these upshifts. I really don't know which produced the best gas mileage. It's pretty bad either way. As a rule of thumb, most folks will tell you to expect to see mileage drop by about half with any tow vehicle, even diesel pickups, so don't be shocked. Good luck guys!
 

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Either way you go with a Curt Brand wireless or wired you will NOT have to cut into anything. There is a thread on here that will detail all the parts you need and where to plug into under the dash for you trailer brake controller.
The other wireless controller is the Tekonsha Prodigy. It has an excellent reputation too.
 
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I recently shared my WDH experiences with @David L a Macan friend from Oz. They are pretty incredible devices. Towing Capacity
 
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