19 replies to this topic

[Vertigo]

Hi all. Love the Forum I've learned a lot. Lurking for 3 years.

Three heavy snowfalls in Denver this winter have proved to much for any 2wd vehicle.

Predictably one of the local news stations reported that awd car and 4x4 sales have jumped more than 10%.

However during the first storm I noticed a couple Subarus and trucks lose traction and spin one front and one back tire.

How many unmodified cars and trucks can move forward when only one tire has traction?

How many of these will allow all four wheels to spin if none have traction? (Important if in deep snow)

Help complete my list

Front and Rear locker
Mercedes G-wagon
Jeep Wrangler Rubicon
Toyota Land Cruiser (Previous Gen)
Dodge Truck 2500 Power Wagon

Front and Rear Mechanical Limited Slip
Subaru STI
Mitsubishi Evo / 3000gt Vr-4
Dodge Stealth R/T TT
Lamborghini Murcielago

[cosworth bdg]

Mitsubishi EVO all versions in this country ,and important in dust and mud, just like our outback..........

[Canuck]

Well, if your weather was anything like Portland's, I don't think anything short of studded ice-racing tires would be of any help. I haven't seen road conditions like that in a long time.

Portland Car Pinball

[McGuire]

http://www.4x4abc.com

[McGuire]

Originally posted by Canuck
Well, if your weather was anything like Portland's, I don't think anything short of studded ice-racing tires would be of any help. I haven't seen road conditions like that in a long time.

Portland Car Pinball

Whee! The video is kinda fuzzy but I thought I saw a few high-end SUVs in the scrum.

Just goes to show... in bad weather it's far more about driver judgement, skill and experience than any particular AWD/4WD system.

[imaginesix]

Car pinball is all very entertaining but you'd think at some point someone would have enough of the carnage and stand at the top of the hill warning drivers instead of standing around with a beer or a camcorder poking fun at them. It just takes one person.

[CFD Dude]

That's true, but it all depends on whether anyone listens to you when you're waving your arms.

I've tried it to tell people that the road is blocked up ahead before - times where there's accidents , the road's flooded, etc. Half of the drivers don't even bother to slow down to see what what you're waving your arms about. In snow and ice conditions I find that the "I have 4 wheel drive, so I can go through anything" drivers are the worst for ignoring warning signs.

[McGuire]

Originally posted by CFD Dude
In snow and ice conditions I find that the "I have 4 wheel drive, so I can go through anything" drivers are the worst for ignoring warning signs.

Ain't that the truth. You nailed it. The main thing 4WD/AWD provides is a false sense of security for the ignorant. In every sleet or ice storm some dork in a Lexus or Cayenne invariably blows past me in the left lane at 75 mph. I know I will next see him in the ditch or stuck in the guardrail a few miles up the Interstate.


I'm sure you don't need to be told, but a couple of tips for those who haven't driven on snow or ice, in case they suddenly have to:

1. When you feel the ABS or TC operating, SLOW DOWN. They are telling you there is NO GRIP. TC and ABS are great but they do not revoke the laws of physics, nor can they put grip on the pavement that is not there. Civilians are still totally misinformed about TC and ABS. They really do believe that when the ABS kicks in, that means "keep on driving beyond the limit of grip, the ABS will stop you."

2. Glare ice forms when moisture in the air condenses on the pavement. Since overpasses and bridges are cooled from both the top and bottom, the ice will form on that pavement first. Stay off the brake, ease out of the throttle, get everything squared up and take a good look at where the car (not the steering wheel) is actually pointed, because that is where you will be going.

[Ross Stonefeld]

I loved my Renault Alliance in the winter driving of Wisconsin, even if I locked all 4 wheels, it ran out of momentum long before I got to the stop sign. My father's jeep on the otherhand, terrified me.

[GBarclay]

I live in Colorado and must comment on the SUV thing.

Without fail, every SUV I see having trouble on the roads is fitted with all season tires (or Texas plates). All season tires are pathetic in every season, and are especially bad in snow with little or no tread. Surely if you can afford a $40K plus SUV you could also afford some cheap steel wheels and studded snow tires.

I might be one of those people McGuire is complaining about. When everyone is travelling at 25mph because they are running around on all seasons, the Subaru is perfectly capable of doing 40mph or more, because it is on fresh studded snows.

A warning concerning lockers. Electrical and mechanical locking differentials are huge traction aids but can get a novice driver into trouble in a hurry. I had a Jeep Cherokee, and once I added a rear locker the Jeep could get further in RWD than it was ever able to get in 4WD previously. However driving a vehicle with a locker can result in handling that the driver may not be familiar with. The mechanical lockers (like a detroit) rely on a degree of surface friction in order for the locker to lock and unlock. On snow and ice there is not sufficient friction for the locker to "unlock" and as a result the vehicle tends to oversteer under acceleration or cornering.

Adding a mechanical locker to the front axle can make the problem even worse. This can be made more dangerous when driving on partially cleared roads showing pavement through the ice. My Jeep would move an entire lane sometimes as the lockers "locked and unlocked". However a vehicle with front and rear lockers can make it through deep snow where most other vehicles would be stuck spinning wheels.

My wife drives a Subaru STi (on studded Hakkapelitta's) which has LSD's in the diff's. The car is extremely capable in most any road conditions, hampered only by it's low ride height once the snow gets much above 10". The US models come with a center locking diff, that can be left in "auto" mode or manually adjusted to the driver's preferred setting. In really bad snow conditions, I recommend manually adjusting the setting. In "auto" mode the diff senses which axle is spinning, and the diff sends more power to the other axle. In certain snow conditions this can result in the diff reacting a little slowly, and can actually make the vehicle handle worse than when locked in "manual" mode.

A lot of accidents in bad weather could be avoided by better driver training. The Bridgestone winter driving school in Steamboat Springs provides excellent instruction in winter driving that all drivers can benefit from. Or seek out one of the many clubs that run winter ice races at Georgetown lake for some winter driving practice.

[crono33]

once i went to a ice circuit for a couple hours fun with friends. studded tires banned on the circuit (they would destroy it in no time) i was riding a clio williams with half crappy winter tires.
other guys were riding a mix of cars, mostly FWD and one AWD, a lancia delta integrale on non studded winter tires.

due to weather (warm during day and freezing at night) the circuit was like glass, no traction whatsoever. after some laps i found out the only way was to drive on the snow/broken ice on the outside of the track, following totally wrong lines. i was lapping everybody every 3 laps...

the second faster car was an extremely old Renault 5 fitted with new winter tires, which afforded "some" grip.

i ended up smashing against a guy riding a golf 4motion. he was spinning 3 or 4 times every corner and was overall one of the slowest. i tried to overtake him...my clio still carries the scars :-)

never managed to use more than 2nd gear that day.

one night, riding the same clio on the A1 motorway in switzerland, suddenly felt the steering lose any feeling. i was going 120kmh. i lifted off and the engine went on idle... absolutely zero grip. i managed to SLOWLY bleed speed playing the throttle. at the same time, everybody else was zipping by at 120kmh. i bet they didnt realize the conditions. just by sheer miracle, no accident happened at the time


i spent a winter in stockholm with my lancia integrale on summer tires. the AWD transmission of the delta allows incredible levels of tractions. on frozen uphill road i could accelerate much faster that people riding studded tires. but when it came to stopping, it was another story...


bottom line is, type of transmission matters very little when it is very slippery. tires really count. and of course, driving skills. driving on ice or snow really requires practice.

[Dragonfly]

Nothing's gonna save you on bare ice. Even a multidrive military vehicle. Maybe spiked tyres (chains) would provide sufficient grip just to keep on the road.
So if one manages to stop better not try to move again.
I presume people there don't have much experience in bad weather/winter conditions and do not take with enough concern the dangers of driving in such situations.

[fester82]

I've spent most of my life driving in winter conditions. While up in Fairbanks, Alaska, I had my first car equiped with ABS that came complete w/a video explaining the safety advantages. It said just to maintain pressure as opposed to pumping the brakes as before. If you ever get that far north, you will learn the intersections rapidly develop a fine Zamboni sheen as the streets are white for six months and salt doesn't work at -40deg (same in F and C). I've applied moderate pressure and have slid right thru an intersection as all four wheels managed to get locked and the computer concluded I had stopped.

I've driven all types of vehicle drivetrains starting with a convertible Karman Ghia (nothing like driving and scrapping the inside of the windshield half way to school), an old Buick Electra 225, to multiple fwd and 4x4s and conclude as others have stated - it is the contact patch and the driver that makes the difference. I currently have a Pacifica AWD and the fancy 19in rims and Michelin tires suck in the winter even with all wheel drive. I'll muddle my thru this winter, but next year they will be replaced with a decent set of snowtires.

[McGuire]

Originally posted by Ross Stonefeld
I loved my Renault Alliance in the winter driving of Wisconsin, even if I locked all 4 wheels, it ran out of momentum long before I got to the stop sign. My father's jeep on the otherhand, terrified me.

LOL I know exactly what you mean.

The absolute best vehicle for learning to drive on ice & snow is a 2WD pickup with bald tires and a seized wheel cylinder. Every block was another advanced lesson in car control. But when it came time for my children to drive I chickened out on that approach and made them get decent late models with fwd.

[McGuire]

Some may find this interesting... one of the trade papers reported this week that Mercedes-Benz wants to make at least 20% of its passenger car sales this year in 4-Drive models.

[GSX-R]

Lambo LM002 ? or even http://www.baesystem...asp?image=bv206

[naiboz]

One carefull owner...

[GSX-R]

Max speed: 52 kph. 2 knots in water

Not very expensive, finally . I had the chance to drive one for a try on a dry ground. Quite funny. I imagine this should be very efficient for SUV's disappointeds.

[Fat Boy]

This is funny. My best winter car was a Datsun 310. It was an awful car, but was as benign in the handling department as any car you could ever have. I would bust down super snowy roads at 60mph with the front tires spinning like crazy, constantly sliding. Always went in a straight line, though.

Later, I owned a Mazda 323 GTX. That would have been the winner, but I already lived where snow didn't that time. Push the center locking diff button and knock yourself out.

[Greg Locock]

I must admit that various overpowered FWDs were always hysterically funny in the snow. Point and shoot, and a bit of handbrake. Admittedly snow in the UK is some weird mix of snow, water, grit and salt.