I have 18" Pirelli Scorpion Ice & Snows for the winter. They are amazing. I wouldn't even dare running summer tires.

 

Just came back from the trip without chains on the summer tires. Going up the mountain was fine since it wasn't snowing, but coming down it started to snow.... trust me guys.... you need snow chains unless you have winter tires!!!!!!!!!!!!

 

I was asking around on another forum to see for those that put chains on Cayenne. Do they put them on the rear only or all 4 wheels? Although I am still not sure of my question. I will be ordering Thule chains from Vulcantire.com per a member recommendation. They are much cheaper than the dealers and the spike spiders, $159 per pair for my stock 19" and they have these nylon beads to minimize the chances of scratching the rims.

Whatever you do, stay away from tirechain.com, i bought from them last year and they are absolutely by far the worst website I have ever dealt with. I ended up having to dispute the charge thru my credit card company to get my money back!

 

Thanks everyone for their contributions heading to Yosemite, I have one set of Security Chain Company SZ435. Also 2 sets of emergency chains. and nearly new set of Continental dsw06