honerboys

mine do not disengage automatically over 20 MPH - so is something wrong? - i have driven it at about 35 MPH for a half mile or so - but it's a PITA as it won't either upshift or downshift at all

Cold-Gas

It’s your tires 100%
We have two Cayennes at home. My wife drives a 2016 Diesel and I have a 2014 GTS. They are both on Michelin Pilot Alpin 5 SUV winter tires in the winter and they are fantastic in the snow / ice. Being in Northern Canada we get it all from freezing rain to heavy snow storms leaving as much as 18” of snow at a time so far this winter. We live way out in the country on a road they don’t plow very often and have never had any issues getting out where we needed to lock the diffs. Although with the one deep dump we did lift the air suspension to get some extra clearance to get to the main highway. We both find the cars extremely stable and feel very safe and relaxing to drive in the winter.
If you don’t see snow very often maybe you want to get an all weather tire with the mountain snowflake rating on it as your best compromise. Our friends run Toyo Celsius Sport all weather tires on their Cayenne up here as they don’t like changing tires for winter / summer and say they are quite happy with them year round.

PFDGSB

Generally speaking, 4x4 trucks don't work like that. When in 4WD, one tire in the front and one tire in the rear get power. And it's generally the tires with the least traction.

There are options to electronically lock differentials etc., but I'm guessing you weren't talking about that on a 28+ year old truck.

F SANE IL

The Cayenne is so heavy I wouldn't be surprised if it's same weight as a pickup if not more. Not to mention that pickups empty bed is a burnout special. Not sure why you feel it's unstable, I've driven in snow and in wet on my 295/35/21 conti dws without issues. Granted, this tire size is no where ideal for snow, even though they advertise it as DWS Dry Wet Snow. But compared to other vehicles I've driven, I think it's great. Locked 4x4 isn't ideal for going at speeds. Most awd systems just transfer power.

ElSpoon958

It's so funny reading this, because I feel very similar. Very well said/put. I haven't read other comments yet to bias my first reaction to this, but I'm sure someone has mentioned tires already. You didn't mention what kind of tires you have, and what kind of snow are we talking about? For example, I live in Denver, CO. I actually grew up/spent most of my life in small mountain towns thinking it was "just normal" that everyone not only had 4WD vehicles, but also ground clearance, STUDDED snow tires, and a set of tire chains on hand "just in case".

But I'm with you on the expectations of the snow driving performance/experience. And I say this after first being a lazy el cheapo & waiting way too long to take off my summer tires. I took a chance too many times on cold, snowy, icy roads. Luckily I drove as slow as possible and never had an accident.

Then I finally put my set of Blizzaks on and thought to myself, "alright f*** you snow, let's go, it's on now!" to no avail. Granted, these tires are on their last season for sure. They have seen better days. Pure snow or pure summer tires don't have long tread life. Part of the trade off. But I'm not thrilled with how this thing handles. And this is my first Porsche. I thought the Germans knew how to build good, capable snow handling machines. Like, if anyone is doing it right, Porsche should be on that list. And I tried all the settings also, like what gives? OK, I've got "off road mode on", my differential is locked. I don't have PDCC, but I have basically every option you can have on a 2011 Turbo. I thought this thing would rip in the snow. Especially since so many people like to off-road these things too.

Maybe having PDCC would help in the snow as well as regular street handling? I don't know. It's strange. I don't think neither the offroad mode nor the differential lock helped me when we had a deep snow experience lately. Granted, I was doing better than some other vehicles I saw super duper struggling lol but still....

I came to Porsche from Infiniti. I had their ATTESA AWD & brand new "all season" tires with above average snow handling characteristic and yet the handling in the snow was abysmal, disappointing, and downright worrisome at times. I feel slightly more in control with my Cayenne Turbo (from the same year as the old Infiniti), but I have similiar sentiments about the expectations of AWD and offroad suspension and driving mode awesomeness and actual reality.

I got catfished by a car.

Norge911

Being the car won’t shift gear is your warning, don’t drive around w locked diff. It’s meant to be used for short distance and low speed.

nothing is wrong even if car wont limit speed to 20mph,

ElSpoon958

One of my more recent previous cars, good 'ol 2016 Ford Focus ST I got brand new... slapped some brand new Blizzaks or Michelin X-Ice (I forget) on there and the joke was that it went from a FWD torque-steer-prone little brat to "virtual AWD".

As you and everyone have said, I think either Bridgestone Blizzak or Michelin X-Ice or go home.

Visualistics

I turn PSM off on snow and have AT tires and I think it handles as good/better than any of the other AWD/4WD vehicles I’ve driven.

You shouldn’t be locking your diffs when you’re just driving around town. That’s for like crawling over rocks and getting out mud or snow when you’re stuck.

But again, tires are 90% of the equation here. If you’re driving on used up snows or normal all-seasons, you’re going to slide around. The used up snows don’t have any tread to claw into material so they are going to be next to useless if they are too worn.

If you think your Cayenne sucks in the snow, go to a parking lot, turn PSM off and slide around to get a feel for the limits so you can drive safely on the road.

lml999

No, it sounds like you got seduced by a set of cheap used snow tires.

Put on a *new* set of Nokian R5 true winter tires and report back. Then replace them after four years, max.

jbl16

Agreed, worn down winter tires are basically all seasons. Winter tires are recommended to be used down to 4/32". They usually have two wear bars one for snow (4/32) and one for all season (2/32).

Dr. G7

In Wisconsin, annually I exchanged "summer" Michelin Pilot Sports for "winter" Bridgestone Blizzaks. Never messed with the differential locks. x feet snow drifts no challenge. Black ice? Caterpillar treads?

Swear I would have bought a Mercedes Unimog if I stayed in Wisconsin.

Dr. G7

My favorite: Nokian hakkapeliitta. Unpronounceable name.

Dr. G7

Very good luck with Bridgestone Blizzaks

Dr. G7

Yes. Mercedes Unimog.

reneeweiss

My experience with both my Cayenne and Subarus is that when they lose it they lose it and the car goes where it wants to, mostly a big 4 wheel drift and you are just a passenger. I have a set of Blizaaks and Porsche wheels for sale on Rennlist if anyone is interested check them out. I don't go to the mountains any longer so I don't need them. I can't say I loved the Blizzaaks on the freeway, at 70 you feel like you have gummy bears for tires. Perhaps they needed more air then suggested but others I know with other cars have said the same about the gummies but on the other hand they work in the snow, deep or shallow and certainly stop quicker on snow than M&S- pretty important.