OK to mix snow tires front to rear?

For the past two seasons I have been running my 2003 C4S with Dunlop Wintersport M2's front and rear. Lots of fun and no issues but, predictably, the rears are now totally shot while the fronts have plenty of life left in them (a recurring problem with this car). So...I need new rears. THe problem is that it seems that the M2's are no longer available so I have a choice of Blizzak LM25s (I had Blizzaks on my MR2 and liked them) or Pirelli Winter 240's. Both are the same size and price, at least for the rears. Obviously I don't want to buy new front tires unless I really have to, and I had always heard that having different tires was OK as long as they were the same on the same axle. Anyone have any knowledge on the subject? Thanks

I realize that you are looking for an informed answer rather than opinion. I recall reading an explanation of the perils of using two different brands/tread compounds/ tread patterns front vs. rear and the possibility that the fronts might have more grip than the rears in a turn or vice versa causing loss of control. I don't recall the source or this information, sorry. Tirerack?

Thanks. I would agree that changing tire brands might cause a change in the understeer / oversteer characteristics of the car. But I suspect that the car would not handle badly, just differently. I would expect that keeping the tires the same would provide 'optimal' handling but I don't think that having different makes would turn it into a wild thing. Since these are snow tires I am not going to be going crazy with them. But I could also find myself driving them in situations where, although speeds would be low, finding the limit of traction would be easy. Unless I hear something to the contrary I will probably get just the rears (Blizzaks most likely) and see how it feels. If it feels bad then I will spend the money and get the fronts also.

Something about the outer diameters of the wheels is important for the mechanism that does the all wheel drive. I have a C4 and I am trying to be cautious about it too since I don't know for sure. My situation is that I have to replace a damaged tire on the rear, it's taking Tire Rack forever to deliver the replacement, and I gotta get snows on real soon here. When it does come I am wondering how much difference in circumference there will be with the existing rear rubber as compared to the new rubber. If they are out, it might put some bad wear or some other such thing. Again - I'd like to say I probably don't know what I am talking about, but have heard something like this, and I like to err on the side of caution. When the new rubber comes in, I am going to take a measuring tape and measure the old rear rubber circumference and the new rubber circumference and report the difference to the nearest Porsche dealer (500 Km away!), and see if they think it's cool or not. Your situation is different - fronts vs rears. Maybe it's all OK for your situation. I don't know if this helps - but that's my 2 cents.

I'm actually in the same boat you are! I have used the Dunlops, but needed to replace the rears, so went with rear Blizzaks. Personally, I think it's going to be fine. They are both very similar looking winter tires. I think the big risk would to only run winter tires on the back and summer tires in the front. But, obviously, you're smarter than that.

Quotes source post: 5874613

You could always get the new tire shaved to match the old one. The lost mileage on the new one would be cheaper than replacing drivetrain components.

Quotes source post: 5875042

Definitely! I was caught in a very minor snow storm a few years back driving my MR2 Spyder with summer only tires. Despite many years of racing cars, karts and motorcycles I could barely keep the thing on the road - and there was probably less than 1/4" of snow. I was only about 2 miles from work when it started snowing and I honestly wasn't sure I would make it without wrecking the car. I resolved there and then never to drive in the snow with summer only tires again.

You're probably NOT going to be driving that car like a bat outta hell in winter conditions,--thus, you should be able to get away with it. Check the age of those fronts,--as they age they get stiffer and will act a little odd.

No offense Dan, but do you drive much in the snow in CA? I've found, that like summer tires, the winter tires wear at a rate of about two rears per one front. So half the time you have front tires that have a little more tread and are a little older than the rears.

I just ordered the rear Blizzaks and received a message stating that snow tires should be matched. When you read more it basically says that if you are putting snow tires on then you should have snow tires front and rear. I'll try to remember to post my results after some experience with them...which hopefully won't be for a while.

I'll try to remember, too. I won't put them on until mid November (after my last track day - Nov. 8th.)

The tires arrived today - very quick turnaround. This is especially impressive since I didn't pay for the fast shipping and only yesterday they called my wife and told her that they couldn't ship only two tires because I needed to get 4 snow tires or the car would be dangerous. Once she had convinced them that I already had snows on the fronts...and that, yes, the rears wear out faster than the front tires, they agreed to ship.

Update. Finally put the tires on this weekend and everything feels just fine - and I think these ones are much quieter than the ones that I replaced.

I have a 996 gt3 and i live in similar climate you you in NW NJ. i had always tried to match the rear and front winter tires, but could not do so easily for this car. since i wanted to mount the tires on the OEM rims (i have light weight ones for summer, track), i had to go with dunlop wintersport M3 for the rear and wintersport 3D for the front. the treads are a little different but so far so good (i have had them on since the end of Oct). This combo was recommended by Tire Rack. any tire change will alter the handling of the car to some degree. i am sure that only mounting winters in the rear or using significantly different tires left-to-right would be the big no-no's otherwise it is simply a matter of (different) handling. my car does handle a little differently with a little less grip in the back, but that is also likely a reflection of the rears being 275 instead of 295. On the plus side, it is easier to break traction in the back.

I've been having great success with my new Blizzaks on the rear and last year's Wintersports on the front.

Quotes source post: 6115323

what did you pay mounting? I just shelled out $170 at an ETD shop. Seems kind of pricey to me.

Sorry, just saw this thread and you already have your tires. I have Dunlop Wintersport M3's on my BMW. I was going through the same situation where the fronts were fine but the rears were around 50%. This is the minimum recommended point for the snow tires. An email to Tirerack and to Dunlop verified that an option to the M3's are the new Wintersport 3D's. The tread pattern and sidewall construction is similar enough that they can go together. So, I have a pair in my dining room just waiting for an opportunity to mount. I thought I'd post what I found anyway. I'm not familiar with the M2s but if they're similar to the M3s then the 3Ds is a viable alternative.

Quotes source post: 5878101

Actually, while my home is in Santa Barbara, I drive quite a bit in the snow. Just last week I was up at Mammoth in mandatory snow tire or chains areas and getting around quite well with 4 snow tires (Michelin Alpin) on my vehicle. Next week I'm heading up to Oregon and anticipate more snow up there and another rig I have for that trek will have a couple new Michelin Primacy Alpin snow tires but only in the front (that rig is FWD). I have lived in Colorado, Oklahoma, New Hampshire, Massachusetts and all over Germany. I have a lot of time on snow AND ice. My vehicle of choice in the winter is a RWD Porsche with 4 snow tires, and cable chains in the trunk.--just in case. Again, if you're not hoofing it too hard you can get away with it, but more and more snow tire manufacturers are highly recommending that you run the same snow tires all around. This obviously has issues for those of us with 911s as we definitely will go through a set of rears pretty quickly, but the fronts lag behind. The wearing in of these things (snow tires) is such that much of their performance features are lost after about 10,000 miles. The sipes and other unique tread features, as well as aging of the rubber, all work against you over time. Personally,--I wouldn't sweat it,--but then, I've driven over the Alps, and Sierras, Cascades, and the Rockies in the winter season in some pretty deplorable road conditions. I think it's great that you're out there in your 996 driving it in the winter. These things are great in the snow.

Well I put them to the test yesterday. Going to work yesterday I was taking the helix that goes from the Garden State Pkwy to Rt. 80 at about 7am when I felt the car getting a little squirrely. I backed off in and watched the Subaru Outback in front of me lost control and bounce off of the concrete wall. I was on the brakes with the ABS kicking in waiting to see where he was going to end up after bounding off of the wall and, luckily, he stopped leaving enough of a gap for me to squeeze through. While I would like to think that I actually do have decent car control, I have to also give credit to the fact that snow tires DO make a difference in these situations. It�s also nice having a car that gives such good feedback to get that early warning.

The REAL challenge comes from the others out there. You can have the best snow tires in the world on a C4S and then, WHAM, comes some idiot in their 4-wd jeep who thought they could handle everything with well seasoned M+S tires...