Really need to know the series of Cayenne you're asking about. Some yes - some no.

 

It’s a 2018 Cayenne S, 2nd Gen, 958.2. I have used a thule basket and a thule cargo carrier at various times and would like to have the options to use them with my Cayenne (just bought it used a few months ago). If I can’t add rails, I think thule makes a system that connects to the door openings. Appreciate any input you might have.

 

I won't say absolutely you can't add rails - but the expense and difficulty doing it makes it really impractical. The 955/957 series cars came with the needed mounting points in the roof, even if the car didn't have roof-rails. The 958 series didn't - and adding them requires dropping the roof-headliner, and welding brackets to the roof structure, which destroys the paint on the exterior, then drilling holes through the roof for the bolts for the rails. If you mess up the spacing even the tiniest bit things aren't going to fit. I've heard of one person who did this, and they said they'd never do it again since it turned into a massive expensive job.

I'd say look to Thule.

 

I think you be right … waaay too much pain for too little gain. Thanks for your input. While I have you, what’s your opinion about tuning an S to get another 20-40 hp?

 

Thule makes a roof kit specific to your Cayenne. I had to have roof racks and my 2013 came without so I checked into adding and it was way too complicated and expensive. I bought the Thule rack and it is fantastic. Looks good and works great. I carry kayaks, skis and a roof box with no issues. Plus it is easy on, easy off so when I don't need it I can put it in the garage.