Fronts, rears or all 4 corners??

I'd say four snow tires. If you already have at least two snow tires with some life left in them that you want to use, put them on the front and put two new snow tires on the rear. You always want the best tires at the rear, for safety, to reduce the chances of oversteer (a tailspin). Understeer is nature's way of telling you to slow down; oversteer is nature's way of telling you you're going to die :_>

 

Richard is correct and pretty funny.

If you can afford it then having a dedicated set of cheap wheels and studdless snow tires is the safest option. They really do make a huge difference in traction compared to an all-season tire. Otherwise put the newest tires on the rear and drive carefully.

 

you may not have enough tread to get through the winter but you may have plenty of tread for next spring and summer, buy a set of cheap wheels (aluminum or steel your choice) and a set of tires designed for cold weather (aka winter tires). Then you can keep your mild temp tires (aka all season tires) much much longer. If you want to pimp your ride you can also buy a set of winter tires to put on your stock wheels, then next spring buy a set of 17" or 18" wheels with low profile tires to look really stylish but this will greatly hurt your mpgs and be expensive.

michelin x-ice will get you best fuel economy and they'll last forever, but they are expensive and don't perform very well in snow, so they are designed for commuters who drive lots of miles on expressways which are always the first to get snow cleared off them.

most northerners should instead buy general altimax (surprisingly cheap since they're made in Germany), bridgestone blizzak (the new ws70, not the old ws60), if you're buying from tire rack their best value is continental extremeWINTERcontact. Stay away from winter tires from yokohama, Dunlop and goodyear. nokians aren't worth the extra $$, the generals can be studded if you live in northern europe, russia, canada, alaska and a few other states.

buying a different set of wheels will save you the expense of biannual mounting and balancing of your winter tires. If you decide to buy all season tires make sure you lower your deductable to zero because you will get into at least one or two accidents over the winter, if you use winter tires you can keep your regular deductable, I have 1000 broad which means I pay 1000 if its my fault and 0 if its not, I did lower it to 500 broad this winter because my blizzaks are about 5 years old and it is the last season for 2 of them and the second to last for the other 2.

I use 195 65 15 for my winter sets so they can be interchanged with my corolla as well. In addition this gives the prius slightly higher ground clearance, that combined with winter tires ability to stay soft and pliable in extreme cold temperatures means I never get stuck, this is extremely important in a hybrid because you cannot "rock" a hybrid out of deep snow the way you can with a traditional car.

Tires, brakes and suspension work should always be done per axle (pairs), you don't need to do all 4 at once but you must do at least 2. (with the exception of calipers, you can replace just one if it stops working) So if a tire becomes damaged beyond repair you should buy 2 new ones or 1 used tire.

 

John: I guess I'm "old school" This will be my first Winter with my '05 Prius, so I can't give you any benefit of experience, but, I am going with 2 new Michelin Ice non-studded snow tires for the front only. I'm sticking with the same size as the Hankook 724's that are on the back -185/65/15. The Hankooks are almost like new also. I live in north central Minnesota, so I DO expect to be driving on ice/deep snow. I have read the advise about needing all 4 tires to be the same, but I guess I'm stubborn and have to be "shown" that I need them on the back. For wheels, I wanted them to be the same, so I did NOT go with steele wheels, I went with "refurbished" Toyota OEM wheels. They were not much more expensive than the steels and they look very nice. If you want, PM me and I will tell you where I got them. I'll let you know next April if I made a mistake or not. (This is probably where the 4 "same tire" advocates will chime in and say "If you're around next April )
My rationale is to also "extend" the life of my Hankook all-season tires, as next Spring, I plan to put the tires that I have now taken off and put them on the rear, 'cause the last I checked the Prius IS front wheel drive and most of the weight is up there in the front, so I expect the front tires to wear more than the rear.

 

I've been doing 2 fronts only on all FWD cars for 25 years with no ill effect. You can usually get x1.5 from rear tire, so if front will go 50K you can expect at least 75K in rear.

Our tire changing usual strategy involves keeping front for 2/3 lifespan and then moving it back. If at that point back still has some usable thread, and conditions are good, it will get put back to front to finish it off. If rear wears first, then you move front to rear and put new fronts.

as mentioned above it is better to use the same tire front/rear, or at least tire with similar thread and traction rating, and never put 2 different tires on the same axle, especially front. Besides being dangerous it can also mess up differential good luck

 

IMHO, stopping power is the most important consideration on ice/snow. Most accidents are caused by the inability to stop. The front wheels do 90% of the braking. If you can only afford two tires right now, put them on the front. I can see Richard's and F8L's points about oversteer, since that is a more dangerous situation, but it is less likely.

 

I learned to drive in a different winter driving culture, with the belief that steering is still more important than braking. With steering and adequate space to maneuver (i.e. good following distance, no tailgating), you can select a path to even more braking distance, and also choose your impact target. Loss of steering will kill you much faster, especially on two-way roads.

When the front and rear tires have significantly different traction, one end of the car stops much faster than the other. When the front stops quickest, what Richard and F8L describe as 'oversteer' is described by others as 'spinout'. For most drivers, this means complete loss of vehicle control.

 

You might be able to get away with just replacing 2 on the Pri, but another concern would be differences in rolling diameter causing problems with the traction control or ABS. The same-size tire from different manufacturers can have significantly-different rolling diameters.

The Pri is most prone to understeer (I've never gotten it to oversteer), so from a traction standpoint, you might be okay with the better tires on the front.

I prefer to rotate them frequently enough so they wear out at about the same time and then replace all four, even though I have penny-pinching redneck tendencies.

I was originally going to go with a separate set of snow tires but after some research, I thought I'd give the Hankook Optimo H727's a try. I've never seen a tire that does everything so well. It's very quiet, long-wearing, has low rolling resistance, is not too expensive and has amazing winter traction. They've been great all-year tires--it's very nice not to have to worry about a 2nd set.

Eric

 

It is another way to look at things. But IMHO it isn't end of the world if rear starts sliding as it is not that hard to compensate for it.

A couple points:
- there is usually no run off on 2-lane roads
- ABS/traction control are designed to keep wheels from locking
- on fresh snow rear tires have more traction as the follow front tire tracks
- it is not hard to countersteer to compensate for rear slide
- most of spinouts are due to pilot error

 

If you mean Cascade concrete, I agree that it is a special rare-form curse on drivers.

 

I learned winter driving and skiing elsewhere, then moved to the Cascade Concrete zone later.

Remember that much of this advice must be aimed at typical drivers, not good winter drivers.

On the way to "grandma's house" for Thanksgiving, I had the uncomfortable experience of going around a corner in terrible traction conditions to encounter an oncoming 3-vehicle tangle occupying all lanes. All rigs managed to not hit each other, but only the tractor-trailer combination and myself remained in sufficient control to stay on the road. The convertible that spun out a few feet after passing the truck left one side of the road, the SUV behind them left the other side.

I probably didn't breathe the whole time the truck was in my lane, and saluted him for not hitting anything and not jackknifing through those maneuvers. The other two drivers failed at much simpler tasks.