My experience and options and perspectives
I have had a limited slip Ford I'll discuss at the bottom ALOT because it was a love hate disappointment for me.
Well I live here in the city of Colorado Springs CO.
Here, people with front wheel drive get around fine and people who live in the surrounding mountain or plains areas where snow and snow removal services can be more brutal, they often have either 4 wheel drive or all wheel drive and yet also have front wheel drive vehicles that meet their needs most of the time and are cheaper to operate and also gas mileage.
Let's not forget that front wheel drive often is so good in snow because the engine transmission weight is right over the driving wheels in this configuration.
So an extended van will have more weight over the rear driving wheels so will be better than a regular van in snow and ice.
Yet front wheel drive vehicles can get stuck in deep snow, they have low ground clearance and the deep snow can snow plow raise the car up off the ground.
in the old days before front wheel drive was dominant, we did get around with rear wheel drive and made it work. However it was definitely more difficult especially on hills and the rear wheel drive vehicles that are very light in the back, like pickup trucks, were and are the worse. Yet we still have 2 wheel drive pickup trucks in town in the winter.
They are just more likely to get stuck especially on a hill or if the tires are balding.
Some buy sand bags and put them in the back of their pickup truck for 2x2's.
Some people who live in the city, had small front wheel drive cars, replaced the vehicle with 4x4 bigger vehicles and were disappointed because the 4x4 is rear wheel drive until you turn on the 4x4 and they just felt more satisfied and safer with full time front wheel drive.
Yet it's no reason to get rid of the vehicle, you just are more careful and selective of when to not drive it and also avoid streets with steep hills etc.
Here, the tire stores mostly sell all season tires tread and I can't say that I've noticed snow tires being better than that although I suppose tests show they are. I know studded snow tires can be very effective but I don't believe they are legal anymore as they are hard on dry roads and wear down the studs quickly and highway speeds can throw some of them out.
I've often kept a plastic milk or juice jug full of sand or cat litter in the trunk in winter months as if you get stuck on ice, sprinkling it in the tires path can make a miracle difference for traction and oddly enough, you can't get dirt from the ground when the ground is frozen.
Tire chains or cable chains can be very effective even for rear wheel drive.
I did own a 1993 Ford Ranger pickup that was rear wheel drive but had the limited slip.
My experience with limited slip:
Although that limited slip used these friction discs and with say 80,000 miles, there was very little action from the discs were a bit worn.
So I bought a rebuild kit for that had new discs for about $60 and had to take the spider gear cage out to replace these discs but I was able to do it myself.
It was a messy job and the discs go in tight PITA but figured a way to do it from the internet.
ALSO I found that there were I think 2 spacers that seemed to be an after thought by the designers so I took those out and put in the 2 best used discs in their place and also added the friction modifying additive that's required.
Then I had great limited slip action and it did shudder some when turning on dry roads till it settled down after say 100 miles.
BUT I was a bit rough on the limited slip, spinning the tires and gunning the gas pedal for fun in the snow and so within say 25K miles, the friction plates were worn down and limited action was becoming non existence.
SO I'm very disappointed in the friction plates limited slip differentials.
YET they are whimpy But have their place. From what I found from research and use is they are more designed for not being abused.
When the limited didn't do much anymore, I wasn't going to go through the day or two work to put new discs in again and the Ranger got rear ended years later and totaled.
Here in CO, a 4x2 pickup certainly isn't work as much as a 4x4 yet I've heard in say TX, 4x4's can sell for just a bit more than 4x2's as they don't need the 4x4 as much. Heard some people buying their 4x4 truck in TX and driving it here in CO to use or resell.
Does anyone know if Ford still uses these friction discs?
Do other makers use these as well that wear out WAY TOO soon?!
They are very good on surfaces where the difference of traction between the 2 wheels is very close. So of you are racing on pavement with a powerful engine that can cause one wheel to spin, these friction plates are always "on" and are strong enough to keep the other wheel from spinning since the traction is almost the same for both. The same is true if BOTH tires are on snow or ice.
BUT if the traction is quite different between the two wheels, these friction plates can't hold them together(that's why they can allow the wheels to turn separate around corners), so say if one tire is on snow or ice and the other is on bare pavement, then the limited slip can't hold them together and one will still spin yet give some limited friction to the other....
So the lockers don't have this problem, they lock both wheels together so perfect for rock climbing and really everything Except many lockers are automatic but not instant, they require one wheel to get spinning first for the centrifugal force to then automatically engage so in that case the limited slip is superior to a degree because on all the time immediately and so would win the drag race etc UNLESS the locker is a manual turn on locker where you push a button first to engage.
Well the limited slip does help when it's working well in snow and ice from getting stuck yet rivals or perhaps is not as good as front wheel drive.
Yes the limited slip can cause the rear to swing out and away from your control but only if you romp on the gas pedal which can be fun if you know how to correct with steering so experienced drivers would know to ease up on the gas to stop the phenominum but an inexperienced driver could might not know the cause and keep giving the gas and then loose control and possibly crash say at highway speeds would be very dangerous.
I have no experience with lockers but I'd guess that automatic lockers that require some tire spinning to engage might be the best because they don't wear out crazy fast like friction discs did for me.
But my van is extended and I live in the city and I'll be just fine and can always get cable chains if I think I'll need them.
Lockers are expensive to buy and put in from what I've seen and I don't live on a hill and here in CO, our winters have become more mild, 4x4ers seem to pray for snow that doesn't come often enough for them to turn it on.
If I lived on a hill, I'd first consider what I can do to make the hill better for everyone instead of focusing on one vehicle and go outward from there on considerations.
Others who live on a hill, just park the 4x2 vehicle at the bottom of the hill and walk up when the snow gets too bad. Of course here in CO, the snow can all be melted within a week and just a few days on the roads.