Unbelievably poor performance on snow

As I always feel the need to point out in threads like these, we've had zero problems with traction control in the 3 winters that we've had the car. For all three of those winters, we had the stock Integrities on the car running at moderate pressure (40/38). The winters up here (CT/MA) aren't nearly as bad as what you get out in MN, but I've never experienced anything close to the problems that people describe on these boards. My experiences have been on fresh snow, packed snow, ice, and wet roads. The tires definitely slip a bit more on snow and ice, but nothing that can't be tolerated with slowing down and driving a little more carefully.

I write this not to criticize anyone's driving style, but just to point out that I really don't understand what's causing such wild differences in driving experience with the Prius.

 

There seem to be two variations of the traction control. Some people have complained for years they get onto something slick and the tires just stop, or at best creep slowly. But others, including me, have had nothing out of the ordinary. For my car, it spins, grips, spins, grips like you expect traction control to do (when it spins and loses traction, it brakes the wheel and you regain traction for a time). You shouldn't need to be very gentle on the throttle, that probably means you're avoiding the traction control altogether (although it's not a bad idea, and was needed before TC).

I grew up in northern MN with RWD and FWD cars, and my last car was a Subaru (AWD), I've always enjoyed driving in the snow and trying to make cars slide just a little. So I've had a bit of experience with snow and traction. I've deliberately taken my Prius out on the steepest hills I can find around here during snowstorms and it behaves like any FWD car would behave or better (with OEM Integrity tires, now at 26K miles of wear on them). But Jayman from Winnipeg, who has probably more snow and vehicle experience than me, has Prius problems like others here have said. That was helped by putting on snow tires, but I think there must be two different traction-control programs that Toyota uses for the Prius. I don't have ESC (electronic stability control), I'm not sure if that makes a difference. Can you spin a cookie (or donut, depending on locale) if you put the car in reverse on a snowy parking lot?

 

Has anyone had experience with Bridgestone Tires (the ones that come on the Touring Model) in the snow and ice? Almost all of the bad comments are about the stock tires that come with the non-Touring models or don't mention what tire they are using (if not snow tires).

 

I have to echo the previous post. We are into our second winter on the original tires. North west snow is very slippery, compared to other parts of the country. While it doesn't match the Subaru, the Prius has gotten us through several bouts of snow, including a long trip to New Mexico and back in the winter with snow virtually all the way. Good Nokians will be my choice when it is time for a change, but I think operator error plays a part here.

Icarus

 

Thanks for the confirmation.

Actually I disagree. I've lived in both MN and CT, and while the temperatures in CT are not nearly as cold, and the snow doesn't last as long, the snow tends to be much more slushy and slippery and more easily packs into ice. When the temperature is safely below freezing (less than 20'F), the snow tends to be drier and gives better grip for driving. At -30'F you can kick a chunk of snow and it sounds like a tin can as it bounces over the pavement.

The first snowfall of the year is also often slushy and slippery. People blame the accidents in the beginning of winter on drivers moving into the area or people 'forgetting' how to drive on snow, and there might be some of that, but really, the snowfalls at the start and end of the winter season are more dangerous in general because the snow is slicker than snow at really cold temperatures.

I still think there's different programs in different versions of the Prius. It would be interesting to swap drivers in one of these cases and see if we could narrow it down.

 

Earlier someone mentioned jayman. Remember that he is driving an earlier Prius, and they have a lot touchier traction control.

Tom

 

No, it does not. I have never noticed anything like a brake being applied to a poor traction wheel on my Prius. My FJ Cruiser, on the other hand, *does* have that feature.

With the studless snow tires on my Cruiser, one side can be on glare ice, the other on dry pavement. With the transfer in 2H, I can step on the gas, the electric brake boost pump buzzes, the traction light starts blinking, and away I go with no drama at all

With high traction, aggressive, studded snow tires, my Prius has better traction on icy roads than my FJ with studless snow tires. I got my Goodyear Nordic from Canadian Tire, it's the same as the Goodyear Ultra Grip 500 sold in the EU

Goodyear Eur-Winter Tire-UltraGrip 500

If you click on "Profile" a Flash movie loads that explains the tire construction and benefits. This is a noisy tire on dry roads, but the outstanding winter traction is worth it

 

I'm surprised the OP is complaining about a relatively new Prius. I testdrove a new Prius back in April, when there was still a bit of snow around. I thought it had far superior TC behavior compared to my 2004

When I first got my '04, the winter tires were backordered. On the OEM's, my Prius came to a stop right in the middle of the intersection at Waverly and Bishop Grandin, I was south on Waverly in the left turn lane, to head east on Bishop

The car just stopped. Other cars were moving with some wheelspin. I tried rocking, being gentle with the gas, flooring the gas and cursing the car, nothing worked. I know how to drive in winter conditions, and that scared me.

I was almost creamed by a semi truck before the damn car started to slowly move again. I figured, either the winter tires come in TODAY, or I drive my Prius back to my dealer and set it (The car and the dealer) on fire

Fortunately, the winter tires arrived soon after. A day and night difference. When I went to the studded tires, an improvement again

 

Jayman is correct. The traction control on the Prius simply modulates power to the wheels. There is no selective braking action.

VSC, on the other hand, does do selective control over individual brakes, but not for the purpose of improving traction. VSC, which is an option, improves the stability of your Prius during maneuvering and under slippery conditions.

Tom

 

Tom

Correct

My FJ also has VSC, EBD, BA, etc.

I was honestly quite a bit worried about the FJ when I first got it. Like the Prius, there is no Trac defeat button. When you shift into 4H, it "detunes" the Trac, but also disables VSC, so I *never* use 4H on the highway

When you shift into 4L, then the Trac and ABS are disabled. You have the option of turning on the four wheel electronic traction control, called "A-TRAC," or locking the rear differential. I tried A-Trac this summer crossing a dry steep ditch, and it's amazing how with one wheel in the air, the brake is applied to it, forcing torque transfer to the wheel on the ground

If Toyota could figure out a way of using the brakes for the Prius Trac, it would have superior winter traction. It's quite clear that Toyota has learned a lot from the Prius, consider how my FJ has electric assist power brakes

 

My integrities performed adequately in the snow until they had about 20,000 miles after that they were ski's.

 

I tried Dolgon's driveway tonight to see if the difficulties climbing it were due to a problem with his car. He has an unusually steep driveway :scared: for this area and I couldn't climb it either unless I was going at least 5 MPH when I turned in. Thinking back now, I don't recall the tires spinning at all when the car refused to climb.

Dolgon only has about 200 miles on his Bridgestone’s. Hopefully after a few hundred more miles they'll have a bit more grip.

Tonight near my home on a hill that's a pain to run or bike up, I came to a complete stop on packed snow and the car had no trouble getting going again.

Does anyone know if the traction control system takes into account how steep the road is in determining when to cut back on the power to the wheels or is it based solely on wheel slippage?

 

We have a 2007 Prius Touring with the Bridgestone tires and have not yet had any issue with snow.

 

Traction control on a Prius does not pay attention to the steepness of the hill. The traction control looks at speed and tire slippage.

It's been snowing here for two weeks. Traction control stopped me dead tonight trying to go up a driveway to a friends house. The driveway isn't terribly steep, but it is uphill, bumpy, and the snow was fairly greasy. My Prius slowed down until it stopped, and then the tires refused to spin. I easily backed down, at which point I could see that each front wheel had excavated a little snow cave. We circled around and went in the back way.

Comparing notes a few minutes later, I found out that my brother failed to go up the same hill with his Honda Accord. His Accord has good snow tires and no traction control, so this is an example where blaming traction control would be unjust. Sure, traction control kept me from going up the hill, but I wasn't going to get there anyway.

Tom

 

Have you tried backing up the driveway yet to see if that works better? We're expecting a couple of inches of snow tonight so you can test it tomorrow morning.

 

Dolgon, here's what I did. I just removed the original 2006 Goodyear Integrities which had 34,000 miles on them. They still had tread, but with the snow we've gotten thusfar this season, I did notice a diminution in traction, that was worrisome. Here in Rochester, NY we get a lot of snow. The Integrities were OK for snows of Jan. '06 through early winter-07, and snows of early winter '07-Spring of '08. Thusfar this year (Fall, '08) I noticed that traction was not good--not acceptable. With care, you can drive safely in snow with Integrities at least until treadwear exceeds some amount--I know, I did it even in blizzard conditions for two seasons--my Integrities were fine--I never got stuck/stranded and I was able to stop safely all the time. Again, I said 'with care'.

For SNOW tires, I just purchased Nokian Hakkepeliitta R snow tires (set of four) from TiresByWeb.com . These are their newest snow tire design. They are considered to be Ultra Low Rolling Resistance tires and I have NOT taken a hit on mileage below the normal lower temp hit that we all experience. My mileage is same as last winter--49.9 mpg. The "R's" were tested north of the Arctic Circle and have aggressive siping and a nonclogging tread design. They are unidirectional treads so they must be placed on the correct side of the car and remain there--no side-to-side rotation. They cost about $540 delivered to my door. I had them mounted on my original stock wheels with the tire pressure sensors so that the TPMS feature would be functional (early warning) during winter inclement weather, when I'd prefer NOT to encounter a flat tire/underpressure tire. I had the Nokian's mounted by the Toyota dealer where I bought the car--they had the best price by far--$59.95 plus tax complete!

To avoid changing the tires or reprogramming the TPM system in the Spring when I remove the tires (to prolong tread life), I have purchased a stock set of wheels with brand new Goodyear Integrities, tire pressure monitor sensors, lugnuts, center caps and trim rings on E-Bay for $660 shipping included. I will cover the TPMS light with a piece of black tape and look at my tires' inflation more often than I do now. Plus I will store the winter snows right next to the Prius in my garage--that may be sufficient to keep the TPMS light off much of the time, particularly for short trips.

The Nokian's are supposed to have an estimated life of about 60,000 miles. Driving them 5 or 6 months a year at 1,000 miles per month (10 years of life), I'm sure I will not wear them out. I can rotate to Integrities in the Summer right in my own garage and put the snows back on in the Fall--no more switch-out costs. When it comes time to replace this 2nd set of Integrities, I will most likely have mounted on the E-Bay rims a set of Goodyear ComfortTreds or Michelins or any one of the numerous brands/types mentioned often here on PriusChat (good general purpose tires).

I hope this information helps.

 

I'm hoping my new tires will make a difference, but I've found the combination of Integrities, wet snow, and a 2004 without VSC to be utterly useless. With the steepness of hills around here, and the high percentage of drivers without snow tires, Silver stays parked under his blanket of snow. I walk most everywhere anyway, and snow here is unusual, so it's not a big deal. Still, I wouldn't even think of driving through mountain passes in winter.

 

Wow,

What a cornucopia of problems with modern automotive technology when you live in snowy climes! Makes me glad I don't have the hassle that some describe in these posts when living in Southern California. Instead we have a whole range of other events to deal with, from raging brush fires in late summer to mud slides in winter!

One thing puzzles me, however. People have mentioned that the Prius, when on a hill with packed snow/black ice simply comes to a stop, generating zero torque, since the traction control prevents wheel spin. Is that really so, or is there a tendency for wheel-spin to occur which is modulated by the TC. It seems to be a bummer if everything in effect dies, with no traction whatever. There must be some way in which the TC programming can affect this.

 

There must be some torque to the drive wheels, otherwise there would be no way to detect slippage. My experience with the newer Prius is that the car will continue to provide some drive, in short pulses, even after you come to a stop. The problem is that the amount of drive is so low that you can't really feel the spin, nor will it burn down through to something more solid.

If you can keep your Prius moving, then the amount of drive is considerably higher. Once you stop, the drive is very low.

Tom