What's the problem?

I have a 2005 Subaru LL Bean edition Outback. It’s a 6 cylinder with a high perf engine. Whenever I get on snowy or slippery pavement the back end wants to spin out and I can’t seem to keep the car on the road and must slow down to about 25 mph even though everyone else is passing me. I’ve had three sets of tires now and nothing seems to correct the problem. Any ideas what’s wrong?

Too high air pressure in the rear tires? If you’ve got some limited slip in the rear differential, that could produce this effect too.

You don’t report loss of traction in the front at the same time. I’m not familiar with the Soobie system, but if there’s an interaxle differential (full time AWD) without some Torson system involved, the torque will just spin out to whatever axle has the least traction. If this is the case, there’s surely a 4WD LOCK position for you to engage.

Get the wheel alignment checked for starters.
I always check tire pressure after anyone works on my wheels.

Manual or automatic transmission? Mileage on the car?

What kind of tires are you putting on the car? All season? High performance? Winter?

Are the rear wheels spinning when you try to accelerate, or is the rear end sliding when you go around a corner?

Does this happen on wet roads or just in the snow?

Yes, that model does have a Limited Slip Differential, so I would suggest having that checked. It is possible that the LSD is “grabbing”.

The other suspects are indeed the inflation pressure of the rear tires (they are supposed to have about 1-2 lbs less pressure than the fronts on that model). I also have a 6-cylinder Outback, and I use 33 lbs in the front tires/32 in the rear.

Is it possible that you are using the inflation pressure listed on the tire sidewall, rather than what is listed on the driver’s door jamb? If so, that is the problem!

Rear alignment is also something that should be checked.

Also, please tell us which brand/model of tires you are using.

If you are using the same model tire that the car originally came equipped with–namely the Bridgestone Potenza RE-92–that is likely to be the problem. Those tires are incredibly dangerous in winter conditions, and I cannot fathom how Subaru ever thought that these tires would be acceptable for winter driving. After I rid my car of those crappy Bridgestone Potenza RE-92 tires, I never again had any difficulty with winter traction on my 6-cylinder Outback.

Thank you for your reply. I didn’t mention that this problem is definitely worse when I have passengers in the back seat or some weight in the back. I did get the Bridgestone tires off and replaced them with another set of speed rated high performance tires and it hasn’t made a difference. I own two other Subaru vehicles so I know how it should perform. If only my dealership could figure this out!

What inflation pressures are you using???
What is the specific brand and model of the “speed-rated high performance tires” that you are currently using?

You have two other Subarus with high performance tires which perform well in snow, ice, and rainy conditions?!
If the rear brakes are not fully releasing, that condition could contribute to the lack of traction.

“Replaced them with another set of speed rated high performance tires”

The tires may be the problem. High performance speed rated tires typically make not a good snow tire.

Please tell use what tire is on the car.

How about a set of winter tires and their own rims if you can afford it?
I see Goodyear Tripletreads are available for the vehicle, so that might be your best bet if you don’t want to worry about storing an extra set of rims/tires