[BigSkyTL]

I was travelin' the highway the other day, and i got behind a NICE MDX, (bran knew, white and tinted) COOOOOL, i was excited, because Im thinkin' about buyin' one! so we're goin' up this small hill and at the end of it, the thing starts fishtailin'. It was REALLLY icey, but we were only goin about 50 MPH, i was worried for the driver, but more than that shocked about the MDX; An Acura?? -having a tough time on ice??? I couldn't believe it.

Anyway, the guy slid off the road, and into the median. I pulled over, and watched him try and get out, he finally saw me, got out and asked for help. I pulled him out, and asked him if these MDXs are this poor on ice or what? He said he was a little tired but i think it was just an excuse for his inability to drive on ice, and maybe MDXs poor technology in handling ice. He was also pretty pi$$ed about the mile marker that he side-swiped. (OUCH!!) Now he's got a nice white MDX with a greenish streak/dent on his passenger side.

Anyone else have problems on ice like that? For me, handling on snow/ice is something that's very important. Do MDXs have only TCS or do they have some form of AWD?

Anyway, my impression of MDX has been tainted

 

[wamiller]

No problems here

I took mine to Colorado for a week back in January and had no trouble at all. We went through a big ice storm in the Texas Panhandle on the way and the 'X never missed a beat. We rolled along at 60-70 mph. Of course I couldn't have stopped or reacted quickly to any problems at that speed but thankfully the road was fairly deserted. When you still have hours to go and it is getting late you do what you gotta do!

 

[NaNaLi]

ICE is ICE!!! Yikes...

It doesn't matter what you have/driving. If you loose control while doing 50 mls per hour on ice, you start praying. Even if you have a $150.000.00 Porshe. On a snowy condition, see Chuck540's review below.

 

[ghost]

Today was a big rollover day here in northern Minnesota - passed an ambulance on its side and several SUV's in ditches. The first big storm and unseasoned drivers usually brings this on (good thing it didn't happen over the weekend).

I took it easy - the MDX performed admirable, nary a slip or a slide. The MDX VTM system kicks in when it detects slippage to power the rear wheels - I'm wondering how this fellow got his X to fishtail, seems like that would be hard to do (unless he flipped his steering wheel too quickly).

As mentioned, you do have to know how to drive on ice - don't think I'd blame this one on the car...

 

[remery]

The most important winter driving safety equipment is behind the wheel not under the chassis or hood. The MDX is a very safe vehicle in slippery conditions but not idiot-proof as ghost alluded to.

 

[Drew]

The MDX VTM system kicks in when it detects slippage to power the rear wheels - I'm wondering how this fellow got his X to fishtail, seems like that would be hard to do (unless he flipped his steering wheel too quickly).

That is the exact reason why the fishtailing could've occured. Here's why. When the guy was travelling uphill, the weight was transferred to the rear. As such, the front wheels would've started slipping more. This would've prompted the VTM-4 system to transfer more power to the rear wheels. With more power on the rear due sudden power transfer, the uphill slope, the MDX's front bias weight distribution (only 43% of the vehicle's weight in front) and AWD system, this would've caused the rear wheels to spin and break free even though the hill would've distributed some weight to the vehicle's rear end. Whenever a tire breaks free and spins, it looses directional stability and as such, the tail would've started sliding wide. If you don't countersteer quickly enough (most drivers have no clue how to deal with oversteer) or back off the power enough (backing off too much can also cause problems) you'll lose control. This seems to be exactly what happened here.

Here's an experiment...find a snow covered uphill slope and drive onto it. When you're midway up the slope, stop completely. Next, try to accelerate like you normally would. It is likely that you'll find the rear end starting to get loose. This is one of the main problems with vehicles with a front wheel biased AWD system (not limited to the MDX). Stability control and traction control would've helped significantly here by slowing down the spinning rear wheels until traction was restored.

Would winter tires have helped, yes, because it raises the tires tractive limit higher. However, it is still possible for this to occur, albeit at a higher speed.

Good luck...

 

[proskunetes]

50 MPH on an icy road sounds like an accident waiting to happen... I think that fact in itself would support Ghost's theory more than Drew's...

I guess some people are more "sorry than safe."

 

[remery]

...Would winter tires have helped, yes, because it raises the tires tractive limit higher. However, it is still possible for this to occur, albeit at a higher speed.
Good luck...

Drew,
I am assuming you are the same Drew as is the moderator for this type of discussion over on Edmonds but just curious. Would winter tires without studs really improve the tractive limit on ice compared to all M&S tires? I know it's true for snow because of the deeper cleats but how would this help on ice as was mentioned in the original post. Also would the tire tread compound affect traction?

 

[Drew]

50 MPH on an icy road sounds like an accident waiting to happen... I think that fact in itself would support Ghost's theory more than Drew's...

I guess some people are more "sorry than safe."

Oh of course speed exacerbates what I mentioned even more since everything happens so much quicker that you may not be able to regain control.

 

[Drew]

Drew,
I am assuming you are the same Drew as is the moderator for this type of discussion over on Edmonds but just curious. Would winter tires without studs really improve the tractive limit on ice compared to all M&S tires? I know it's true for snow because of the deeper cleats but how would this help on ice as was mentioned in the original post. Also would the tire tread compound affect traction?

Yes, that's me, but I'm no longer with Edmunds.

Yes, the new generation of studless winter tires have a much softer rubber/silica compound that are structurally designed to stick to snow and ice. Of course, there are varying performances of different winter tires, so one has to choose a good make/model too. In contrast, the old winter tires used to have deep groves in order to try to "bite" the snow instead of sticking on it. This did not work as well. However, they did last longer even if you were to drive them on dry roads.

Studs are only good in certain conditions, that is, roads that are snow packed. Some ice at the bottom under the snow cover is not a problem usually. The studs help to dig into this base and grip. However, in light snow or no snow, running studs is not only bad for the road but it is deterimental to handling. This is the case because the studs reduce the tire's (rubber) surface area and hence you're riding on little (slippery) bits of metal instead. This is why I would rather go with snow chains/cables for most situations rather than run studs.

Over in Germany, Sweden and Finland, most of the roads aren't completely plowed in the winter. As such, during the winter months, people can simply put on their set of studded and or chained winter tires and run them all winter long without any problems. These road conditions are also why you see so many rally car drivers from those regions of the world.

 

[qgu]

I have experienced fishtailing last winter when I tried to make a turn in an ice-covered parking lot with speed < 10 mph. I have also noticed my ABS got invoked when I tried to stop at a red light with speed < 40 mph on a snow covered street. My MDX is equipped with Goodyear tires.

My Quest Van with new General Tires never gave me any trouble at simular driving conditions. Therefore, I am leading towards the belief that those Goodyear tires are not good on icy conditions. I drive with extra caution when my MDX gets into slippery condition. 4WD may give you some added traction but the most important thing is still a set of good tires. Unfortunately those Goodyears are not good enough.

 

[jfp252]

Friction is equal to the Normal force times mu - the coefficient of friction. Ice has a mu of essentially zero, therefore no friction. No friction means no stopping. It doesn't matter if you're driving an MDX or a snow plow, a vehicle traveling at 50 mph on ice is simply not going to be stable or stop on a dime. My MDX came with tires, not ice skates.

 

[Drew]

It probably wasn't glare ice. Note that the original post said "we were only going 50 mph", so obviously the conditions were good enough that others were also travelling around the same speed, whether this was too fast or not (it appears to may have been), it's tough to tell without actually being there

 

[frostyra]

NO 4WD or AWD system is any better on ice -- we're talking glare ice or black ice here -- than 2WD. The only things that can help you in these icy conditions are: 1) slow speed, 2) driving skill with well-practiced responses that are almost automatic, and 3) luck!

 

[proskunetes]

BigskyTL,
When you helped the guy, did you notice what kind of tires he had? Do you know if they were they Michelins or Goodyears? Or can you remember if you noticed a roof rack/base carrier on the top of his MDX?

By the way, the MDX does have a AWD system that engages when you need it. Its too complicated for a average guy like me to describe, but I do believe the manual says somewhere not to go 50 mph on ice. The name of the manual is "MDX for dummies."

 

[donsev]

For those who are interested...

Here are some articles on winter tires and the enhanced grip of their tread design/compounds:

http://www.motortrend.com/jan00/ccwinter/1.html

http://www.tirerack.com/winter/tech/faqs.html

http://www.tirerack.com/winter/features/notenough.html

(BTW, does anyone recall a recent article that directly compared 2WD vs 4WD vs Winter tires. They used the MB E430 and E430 4Matic, and Audi A6 and A6 Quattro both with and w/o winter tires. It was an excellent article but I don't remember where I saw it.)

(For what it's worth, the conclusion was that the winter tires enhanced snow/ice road condition performance more than the 4wd did)

 

[ghost]

Snow day!

Well all the schools and lots of the businesses are shut down here today, but not my dentist appointment or curling match, so I'm headed out.

Heard a great comment on the radio this morning - 4WD will get you anywhere, it just won't get you stopped...

 

[proskunetes]

Is "curling" that thing where you slide the oval shaped bowling ball with a handle down the ice and sweep in front of it?

 

[ghost]

Is "curling" that thing where you slide the oval shaped bowling ball with a handle down the ice and sweep in front of it?

Yup, you throw a 45 lb chunk of granite down an ice lane, and hope it stops where you want it to. You give it a twist at the end to put a slow rotation on it so it 'curls'; and the broom guys can speed it up or take the curl out.

It's very strange - I just joined the league this fall, and all four of us are new at it; thus we get killed every week. The people that actually know what they're doing are extraordinarily good at it.

At the end, you say "Good Curling."

 

[BigSkyTL]

Frostyra: I agree, when you're on shear ice (like we were) it doesn't matter if you have 4WD (like I do on the F250) or AWD (the MDX), BUT, some all-wheel drive systems (or 4WD) are definitely more capable at assisting the driver to handle icey/poor road conditions than those without.

I believe if you took to good (not expert) drivers with an average amount of driving experience on icey roads, and put one in a Kia Sephia, and the other in an Acura TL, i think the overall "driving experience" on dangerously icey roads would be more enjoyable in the TL. Simply because of the technology thats in a TL of handling tires losing grip, power transfer, weight distribution; --the TCS system -- exists, and is there to enhance driving pleasure, confidence and safety.

My point (and question) of this thread was does that MDX handle well on ice for the type of vehicle it is. I understand totally that there are many factors that may have played a part in this accident; like fatigue of driver, poor judgement, weather (obviously), inexperience, tires,.... But i guess the question is, could a better, more experienced driver could have avoided this accident under similar circumstances and the same vehicle? Or is the vehicle's AWD system just not as advanced as it could be?

Tires? I didn't look at the guys tires, but yes, he did have a rack on top of his vehicle with skis in it. Like I say, it was a really nice ride. I know my truck came with Goodyears, and I did NOT like how they handled snow/ice, so I switched to Yokohama, and I've been very pleased.

Great info here though, thanks