Chas2

I read this article and it seems that they had real problems with the MDX SHAWD in snow. Has anyone had this problem? Here is the excerpt of the SHAWD problems. Granted, 50 cms is a lot snow....


http://www.globeauto.com/servlet/sto...mdx07/BNStory/

The new MDX can keep up with most other similar SUVs and is probably better through the turns than many of them, thanks to its SH-AWD system.

But not in the snow. With about 50 cm of the white stuff on my street in Delta, B.C., I was shocked to discover that the MDX could barely get out of its own way and really struggled on compacted ice and those wonderful frozen potholes and miniature gullies that build up in intersections.

The problem seems to be within the SH-AWD system, which programs the engine to re-direct power when any of the driving wheels start to slip. But it does so in a way that is meant to stabilize the vehicle during high-speed cornering, not in the middle of knee-deep snow or on an icy side-street.

What happens is that the entire system stops producing power — momentarily — and the vehicle essentially has to start over. Just when you need a bit of oomph and want to get the power down, the system shuts down and re-sets.

The key to driving in the snow, as most Canadians know, is to keep moving. Stop and you're asking for trouble. With the MDX, when the front — or rear — driving wheels start to spin, the vehicle bogs right down. I hasten to add that my test car was equipped with SUV-specific, all-season tires (Michelin Latitude) and maybe that was the problem.

Whatever, the SH-AWD system is first and foremost a performance feature, and although I was warm and comfy in my MDX and could watch movies and listen to a good quality stereo, all that technology was for naught when the rubber tried to hit the road.

Maybe different tires would have helped, and I never did actually get irretrievably stuck, but, in all honesty, I expected better from an AWD sport-ute.

iforyou

iTrader: (1)

hmm....that person didn't talk about the VSA system. In most cases and in most cars, by turning off the VSA system (or whatever it's called), it will help a whole lot in the snow. The traction control system within the VSA simply brakes each individual wheel or apply less throttle whenever slippage is detected. And this causes a lot of problems in the snow. Anyways, that author brought out some good points. It's true that many AWD systems out there are no longer made for getting you out of trouble but are mainly for enhancing performance/handling. Some examples would be Nissan GTR and many Audi's.

UW RL

As many of you know, the state of Washington just got hit by another big snow storm this week. Icy roads and snow are creating a lot of problems for a lot of drivers out there. Many people choose to abandon their cars at the shoulders because they simply can't drive their cars. My RL, with it's stock tires, had zero problems moving on the street. Of course, you still can't drive too fast otherwise you will still lose control unless you are driving a tank. But in my opinion my RL has performed very well in snow and on icy roads. As long as you drive responsibly in snow, you shouldn't have problems with the RL.

By the way, my wife's Audi Q7 has also been excellent in snow and on icy roads. Can't complain the 7th generation quattro, and SH-AWD.

iforyou

iTrader: (1)

UW RL, you will be able to test out your RL in the snow again on Tuesday. They are expecting another storm coming to Vancouver BC and I believe it might affect your area too:

http://vancouver.weatherpage.ca/

"Things are starting to look a little more interesting. An approaching cold front nearing the coast line that was previously expected to be held back by the arctic high pressure ridge is now expected to make landfall on Tuesday bringing a dump of snow to Vancouver according to the latest GFS and NAM models. Preliminary estimates are in the 10 to 20cm range for snowfall accumulations on Tuesday. In the wake of the possible snow on Tuesday it will be dry on Wednesday and Thursday but another Pacific storm could dump another round of snow on the city again next Friday."

By the way, did you have your VSA on or off?

neuronbob

I think it was the tires. My RL with SH-AWD handles awesomely in the snow with decent all-seasons. If he'd had better all-seasons or snows, he would've had less trouble with the MDX, I'm sure. Even so, 50 cm IS a lot of snow (that's over a foot and a half of snow for the metric-challenged).

Qest

Sounds like a combination of summer-oriented all-season tires and VSA. The author should have tried turning VSA off and using proper tires for the conditions.

That said, I'd be surprised if the Mercedes system wasn't better in the snow.

Bartmanhoff

I bought Dunlop WinterSport M3s for my RL this winter...of course it hasn't snowed since I mounted them on the car. If we get any snow this winter (Buffalo NY area), I can report on the Dunlops.

In snow, I found the stock Michelins would stop and go fine, but were were useless in the turns even with only a 1" of snow on the road. The car would plow forward and refuse to turn - I'm guessing that the tires were packing with snow and not clearing well.

With the SHAWD constantly switching which wheel(s) had power, it was not possible to make the car pivot through the turn (ala Subaru WRX - my previous car) using the throttle. Watching the SHAWD display in the 90 degree turns showed that it was sending power to the various wheels, but none had any traction. As it switched almost instantaneously from wheel to wheel, the car (and driver) had no time to react to what the car was trying to do.

Jaysmith2000

I had the opportunity to really test the RL in the snow this week and had no problems with it at all. I didn't have the VSA off either (will in the future though, thanks for the tip).

Riddler2222

I have had no problems with my RL in snow. I was blasting through 8 inches of unplowed roads in early december and the car was tracking great.

iforyou

iTrader: (1)

how i wish I had a SH-AWD equipped car......

RL06tech

I have driven the RL in a couple of wisconsin snows now. Traction in a straight line and up hills is excellent with the standard MXM4. Braking is tire limited and thus mediocre. Turning as well is also tire limited, ergo mediocre. Of interest, in sharp turns from a standstill its easy to induce oversteer which is controlled somewhat by the VSA. Overall snow performance is what is to be expected of any other AWD vehicle with all weather tires. The point others have made about the VSA is completely true, in very slippery conditions its an advantage to turn it off so wheel slip is allowed and the car doesn't bog down. All systems are traction limited (DUH) irregardless of how many tires are driving the car. My ody with snow tires will get stuck on a snowy hill (ie my driveway) but will brake better than my RL in the snow.

RL06tech

The RL's SHAWD calibration is geared for dry and wet pavement. It allows for controlled oversteer in those conditions, acutally its quite nice since a small amount of tail wag is better than terminal understeer when driving enthusiasticly

Rob L

As stated, the system does fine in snow but the stock mcihelins are crappy in many areas and thus one may think the system has issues wiht snow when it is the tires. I would not doubt that this guy simply had junky tires ont he car rather than the system on the MDX being at fault.

lsbuffs

You'll love the Dunlops. Trust me, living in Denver I've unfortunately had plenty of experience with lousy conditions over the past few weeks. I got them last season and couldn't be happier. Night and day difference between the stock Michelins and these snow tires. I didn't feel at all comfortable in snow and ice until I got the M3s. The ride is smooth and quiet, even at 80mph.

bwollen

We have had snow and ice in Seattle area on and off for the past 30 days. My RL handles the snow and ice like a 4 wheel drive SUV. As long as one drives slow so one does not start slipping on the ice, but no car or SUV can handle ice very well.

UW RL

Seattle got more snow last night and this morning. My RL handled fine on the road. The only problem I had was while I was trying to park on the icy parking lot my car wouldn't move for a few seconds, even though the wheels were spinning (VSA ON). I was trying to back up to my favorite spot, but I gave up and ended up parking heading in. The parking lot was covered with snow on top of ice.

Mike_TX

Darn! It's snowing like crazy this morning in the DFW Mid-Cities area, with a couple inches on the ground. And I'm not about to subject my RL to the treachery of other drivers on this skating rink. (Besides, it's clean. )

And I'd really like to try the SH-AWD in snow, too. Darn.
.
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webhead

I drove into the midcities from Dallas without any problems keeping up with the SUVs out there . . .there is a layer of ice on most of the roads

lland

We had a slight snow last night and this morning. Nothing more than some flurries but they left many roads slick and icy. On the way to work, my ABS activated a number of times as I braked over slick roads. On one road in particular, there was a small panel truck in front of me that kept sliding off to the right. My RL tracked straight and true.

LL

dwboston

We got out first real snow of the season here in the Boston area tonight (1"-2" by the time it's over) - as I was driving home around 9 pm the side roads were all lightly coated. The RL was rock solid - the torque distribution readout was very active and I only noticed the VSA light flash a couple of times. The car tracked exactly where I pointed it. I turned the VSA off to climb my driveway which had an inch or so on it and the car went right up with no problems. I'm very impressed with how the Pirelli's handled.

lumpulus

Yup, dwboston and I had the same experience....I was able to experiment a little in the empty parking lot in a big industrial park....SH-AWD is really cool!

The only way I could confuse it was to stomp on the gas from a standing start, this was on 2 inches of snow over a coating of ice. Other than that it went right where I wanted it to.

I was amazed at how much traction I actually had.

neuronbob

How many miles do your Pirellis have on them? Still admiring them from afar....

dwboston

I have about 2,000 miles on them so far. They really seem to have broken in the last 500 miles or so and are very grippy - great for taking the curved Mass Turnpike exit ramps at 50 mph (on dry pavement).

bluemule

Interesting. This past week, Motorweek did a piece on limited slip differentials vs. locking differentials with pickup trucks at Eaton's test track (Directv/satellite.)

http://www.mpt.org/motorweek/autoworld.shtml

I would be very interested in seeing how the RL handles that particular test track...dry pavement on one side and rollers on the other. The pickup truck with the limited slip differential failed miserably...it couldn't climb the incline.

My recollection of the RL's promotional literature is that SHAWD was touted primarily to neutralize steering at higher speeds. However, the other systems should have kicked in for the low speed stuff.

I suspect the OEM's on my car wouldn't handle snow very well, as others have pointed out.

gavine

From my understanding, Limited Slip Differentials are to enhance handling performance, and NOT to help get you out of a slippery situation. I had a RWD 1985 Corolla GT-S with an LSD which handled almost as good as my RL does but in any amount of snow, the car wouldn't even move forward from a stop without a lot of effort. Actually, I think the LSD made it worse because instead of just slipping, the back-end would sway back and forth as the torque got transferred back and forth between the two back wheels.