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Four-wheel drive doesn't repeal the laws of physics. However, many of us are guilty of driving around in snowy and/or icy
conditions without using the proper care. Our Jeeps are ideally suited to driving in the winter and with four-wheel drive,
aggressive tires, straps, and other equipment on board, we are set for those harsh conditions.
The problem arises when we let that knowledge go to our heads and forget some simple winter driving tips. Face it, while
our Jeeps are ideally suited to go in the snow, they aren't really good at stopping in the slop.
Many of the aggressive tires on our Jeeps don't have siping. Most of us don't have ABS simply because we don't trust it to stop us on the trail. The Jeep, by nature, has a short wheelbase and a high center of
gravity. All of these things conspire to make it more difficult to do certain things in the snow.
While we are able to holeshot it out of a stoplight and leave those silly front-wheel-drive cars eating our slush, when
it comes time to stopping at the next light, we're beat.
Generally, the key to winter driving is to do it smoothly, without any abrupt motions. It will be different wherever you
go, and practice is the best thing you can do. That said, here are some more specific tips for going and whoa-ing in the snow
that you can practice in a deserted mall parking lot near you.
Get ready for it
* Narrow tires are the king of the road in the winter, up until the snow gets to your
axles. At that point (and off-road), higher floatation tires are going to be your friends.* If you've got hubs, lock them
in before venturing out, just in case.* When you see snow in the forecast, start telling yourself how four-wheel drive does
nothing to help you stop. It's all driver skill and technique.* Cat litter and ashes help get you unstuck. Carry what you
can fit.
Let's Go!
How you go in the snow all depends on what kind of snow you're in and how deep it is. The
shallower it is, the more forgiving it's going to be. If it's got a crust on it, tread very lightly with minimal abrupt movements
to maximize your chances of staying up top. If it's really deep, the only way to keep going is to keep the engine near peak
horsepower (about 3,000 rpm for the inline-six), but try to keep the wheel speed under control. Wheel speed that's too high
will start freezing the snow in your tires, and wheel speed that's too slow will mean it won't clean out and you'll sink.
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Jeep Snow Safety - Driving While Sloppy
On-road: With our big tires, we can get to the bottom most of the time, so starting isn't that big of
a deal. If there is ice on the bottom, you'll want to keep wheelspin to a minimum when leaving a light or stop sign. As a
general rule, keeping wheelspin down is key, but we all like to have some fun.
Off-road: Treat off-road snow with care when starting. Just like deep mud and sand, feather the clutch
and the throttle for the smoothest launch you are capable of. This will help you not dig down into the evil white stuff and
maintain forward movement. High-floatation tires are the way to go for deep snow, both on- and off-road.
Whoa Now!
When it comes to stopping in the snow, we can't say it enough: leave more following distance
than you might think you need! Whether it's the distance from the soccer-mom mobile or the tree, give yourself enough time.
The soccer-mom mobile has an advanced ABS system and will stop better than you. The tree won't go anywhere, so when you hit it, it'll hurt all that much more.
On road: For shallower snow, ice will be the enemy. Black ice, white ice, whatever color it is, it's dangerous.
Be especially careful at dusk and just after dark, the areas you drove through earlier will likely have ice on them later.
Bridges, due to the cold air cooling them off from below, sometimes have ice on them all day long.
If you do hit ice, don't panic and don't lock up your brakes. It might seem like you'll stop faster if you lock them up,
and sometimes you might. However, with the brakes locked up, you've got no control. Pump the pedal like a human-powered antilock
brake system. Go somewhere the first snowfall or ice storm and practice pumping the pedal. Take it just to the point where
it wants to lockup and pump it there.
Sometimes downshifting helps, if you are smooth with it. If you just dump the clutch to downshift, it'll break you loose.
Be smooth with the clutch and downshifting can dramatically decrease stopping distances as well.
Practice the techniques every year because how often do you need to pump the brakes at the beach in the summer?
Off-road: In shallow snow, driving off-road leaves some leniency for braking technique. If you aren't
going to go off the trail and are leaving a decent following distance, locking the brakes up can be your friend. With the
loose surface under the snow, pumping the brakes can take forever to stop you. Just remember to let up if you start veering
off trail so you can steer again.
Deep snow is the equalizer. If they don't plow or salt where you are after a good snowstorm, there isn't much difference
between stopping on-road or off-road. Locking the brakes up might seem like a good idea, but if you nosedive into the snow
or brake through the crust, you'll have a hard time getting going again. If you have to stop urgently, by all means, lock
them up. But when you don't have to stop quickly, try and do it smoothly without locking the brakes up.
Steering (or swerving)
Whether you are on- or off-road, you will find that four-wheel drive really
only helps at lower speeds. If you're driving at higher speeds, you might as well take it out of four-wheel drive.
On-road: The biggest gripe in snow is pushing while steering. That is, your wheel is cranked all the way
over and you are still going straight. Blipping the throttle can help here. Then again, it can also send you careening that
much faster off the embankment. The idea is that you've got to get some weight off the front tires and get them rotating again
so they will direct you where you want to go. How you do that changes with the situation. Again, practice.
If you are on ice or icy roads, just leave the Jeep in four-wheel drive. With ice, it'll help you steer where you want
to go and also help keep the short-wheelbase Jeep from spinning out.
Off-road: Stay in already-made tracks (as long as they aren't too deep), keep the Jeep in four-wheel drive,
and keep the road speed down if you have to make your own tracks. These three things will combine for the best chance of success.
Those three things and exponentially increasing horsepower, as the snow gets deeper, will keep you moving.
Some advice from Willie Worthy up in the great white north
* Keep away from trees. The snow melts around
trees first because of the heat they put off. The pockets around them will then fill with light wind-driven snow and make
for a real trap!
* Snow to snow makes for the best traction. However, ice to snow does not.
* A tire has to grab snow, hold it in for one rotation so that there is snow-to-snow traction, and then clean itself before
the snow turns to ice. Voids that are too large will not hold snow. If the voids are too small the snow will not get picked
up. Try sticking a snowball to the sidewall of a tire and see how long it stays. Stick snow to some more snow and you have
a snowman. There are some exceptions to this because all snow is different, but, generally speaking, a tire that holds snow
for that rotation is better all around than one that totally cleans out like a Super Swamper Bogger will. They put on great
snow shows, but don't get on a sidehill with them on icy snow!
* You can go downhill a lot easier than uphill. What this means is that maybe you have gone in on a trail that was downhill
most of the way, but you just may not be able to get back out.
* Chains work great in icy snow, but make sure that there is enough clearance for the chains and that they are super tight.
Tie the chains on with heavy rope or really heavy tarp tie-downs. Those cheap spring and lightweight rubber tension devices
just don't do it with big chains that we need for our tires. Double the crosslinks in the chain for safety.
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Tire TIPS for Safety!!
When was the last time you checked your tires' air pressure? Don't remember? Or maybe it was done the last time you had
an oil change (or at least you hope it was). Most people don't care about tire pressure because they don't notice "anything
wrong" with their vehicle. It still seems to go and stop just fine. A similar philosophy seems to apply to winter driving
("I've got four-wheel drive and all-season tires, I'm all set") and worn tires ("They handle fine"). Well it may seem that
way, until you're forced to quickly slow down and/or swerve to avoid an accident, be it on dry, wet or icy pavement. After
attending a tire safety event put on by the folks at the Tire Rack, we fully realized that keeping tabs on the condition of your tires and knowing which ones to use for winter driving make
a huge difference in how your vehicle will react should you need to make an accident avoidance maneuver. The Tire Rack boasts
the largest "one-stop" selection of tires and wheels in the U.S. and it also offers performance accessories such as suspension
and brake upgrades. By using its Web site, consumers can select the correct type and size tires for their ride, depending
on their needs and driving style. Bumping up your wheel size is a no-brainer as the site's configurator automatically shows
only the wheel and tire combinations that will fit a given vehicle. In addition to the considerable amount of products it
offers, the Tire Rack boasts an army of tire experts ready to give advice as well as its own on-site tire testing facility
where said experts push tires to their limits in a safe environment. At the Tire Rack event, we sampled braking on
ice with Jeep Grand Cherokees equipped with three different tire setups, drove a pair of BMW 3 Series coupes (one with correct
tire pressure and one that was low but within proposed government limits) around a track, drove another pair of 330s (one
with snow tires all around and another with them just on the back) and lastly compared new versus well-worn tires on a pair
of minivans by circling around a wet skid pad. In the interest of making this piece user-friendly, we've listed the
factors that affect tire performance and safety, how the Tire Rack had us test them and what you should do to maximize the
safety and performance of your vehicle's link to the road. Tire pressure
When a tire is underinflated,
most of the car's weight is concentrated on the tread that's located just under the sidewalls, rather than being spread out
evenly across the full width of the tire. This means that as the tire rolls, the sidewall gets continually flexed (squished,
if you will) and heats up. This affects both performance and safety. In addition to degrading the handling of the vehicle
(via the mushy steering response courtesy of the flexing sidewalls), a tire that's considerably low on air can blow out due
to the stress from the heat buildup and the constant flexing of the sidewall. For testing the effects that low tire
pressure can have on a vehicle's performance, the Tire Rack had us drive two identical BMW 330Ci automatic coupes —
one with proper tire pressure and the other with 30 percent less than the recommended amount. Why 30 percent less? Because
soon the government is going to require that tire-pressure monitoring systems be standard in all new vehicles, and 30 percent
happens to be the maximum amount that it feels is safe to allow for underinflation. Looking at the two Bimmers side-by-side,
it was hard to tell which one was low on air. The short, stiff sidewalls of the 225/50R16 Goodyear Eagle GT-HRs hid the deficit
well. But when we drove them back-to-back, it was plainly evident which car's tires were underinflated, as the 330Ci's normally
precise handling dynamics were softened, making it seem as if the car had a softer, almost mushy suspension in comparison.
In all fairness, the low-air car didn't feel unsafe, but it certainly didn't inspire driver confidence the way the properly
aired-up car did with its precise handling and steering feedback. We can't overstate this: check your tire pressure
at least once a month, perhaps on the first of the month to make it easy to remember. And while you're at it, give the
tires a once-over and look for uneven wear patterns as well as cut or bulging sidewalls. Irregular wear could signal the need
for an alignment or replacement of worn suspension components. A deep cut or a bubble in the sidewall indicates a potential
weak spot that could lead to a blowout. Lastly, check the tread depth, either with an inexpensive gauge or by using the penny
test. To do the latter, stick a penny upside-down in the middle and outside tread grooves, if you can see Lincoln's whole
head then it's time for new tires. And you don't want to overinflate 'em either, as that won't allow the desired full
tread contact (due to the car riding chiefly on just the center of the tread) and will make the ride stiff. Winter
driving
I have an SUV; do I really need snow tires?
A trio of Jeep Grand Cherokee Limited V8s awaited us on
the ice of an indoor hockey rink. One was fitted with the all-season Bridgestone Dueler H/T D689 tires that came as standard
equipment, another had studless Bridgestone Winter Dueler DM-Z2 tires (essentially Bridgestone's superb Blizzaks that serve
light-truck duty under a different name) and the third was shod with studded snow tires (WinterMaster Plus). The test
consisted of accelerating up to and braking at a set of cones. As expected, the Jeep with the "all-season" rubber had the
most trouble starting and stopping as it scrabbled for grip when the throttle was squeezed and took the longest distance to
come to rest. Although the Jeeps all had traction control and ABS, this exercise emphasized the point that those technologies
can only make the most of the available traction — the systems spastically pulsed the brakes in an attempt to gain traction
to move out and slow down. In contrast to the dicey performance of the stock all-season tires, the studded snows felt grippy
as they bit into the ice under acceleration and braking. The big surprise was when we sampled the studless Dueler DM-Z2 snow
tires. We knew they'd have good grip (well, as good as you can have on ice), and they did. They were just as tenacious as
the studded snows. We highly recommend these for folks who deal with serious winter driving. A word of caution to those
who drive SUVs. Just because you have four-wheel drive doesn't mean you can stop or turn any better than a two-wheel-drive
car. Four-wheel drive allows better motive traction, but when you're off the gas (such as when you need to turn quickly
or stop) it doesn't matter; the laws of physics still apply. If you're tempting fate by driving too fast for the road conditions
and need to turn or stop quickly, you might as well be driving a Mustang. This explains why, during slippery driving, we see
so many SUVs "off road," meaning on the highway median or spun out on the shoulder. Two words of advice to you would-be hotshots:
Slow down. Don't I just need snow tires on the drive wheels for traction?
This myth was laid to rest when
we went out on the dry test track and drove a pair of BMW 330Ci coupes, one with a full set of snow tires (Michelin
Artic-Alpins) and the other with those snows on the back (the 330Ci is rear-drive) and high-performance rubber in front (Michelin
Pilot XGT H4s). This was definitely an eye-opener. Before we ran each car, we shut off the stability control system
and were warned that one of the cars might end up biting us (car-guy talk for a car sliding out of control). Taking the 330
with the four snows through the course, the car felt solid and predictable. Running the 330 with the Pilots in front and Alpins
in the back, the tail wagged increasingly as we zigzagged through the cones and then the car spun 180 degrees. Whoa! We drove
home the point of the test with an exclamation point made in rubber marks on the track. Mismatched tires can (and will,
if pushed) adversely affect a car's handling; with the ends of the car having differing levels of grip, it is more apt to
slide the tail or even spin out. Had we been driving in the snow, the rear tires probably would've had no problem propelling
the car but steering and braking wouldn't fare as well — the high-performance Pilots would've washed out as the snow
would easily pack their small grooves, essentially turning them into slicks. Not good on snow, slush or ice. How
do worn-out tires affect wet weather driving safety?
In order to have traction in the rain, tires need to be able to
channel the water away; that's why there are grooves in the tread. Rain tires, such as the Michelin HydroEdge, have one or
two large grooves running around the tire for that purpose. By channeling the water away, the tread can make contact with
the road (this is good, as it allows steering and braking). In contrast, a well-worn tire doesn't have deep enough grooves
to do this, and so can ride up on the water. This is called aquaplaning or hydroplaning (not good as you won't be able to
steer or brake). To demonstrate this, the Tire Rack had us drive a pair of Ford Windstar minivans — one with
new Michelin HydroEdge tires and the other with the same model of tire only with minimal tread left. We piloted the Windstars
around a large circle that was being "rained" on by sprinklers. By gradually increasing the Windstar's speed, we witnessed
how the van with the good tires could stick to our intended line at around 40 mph while the almost bald ones allowed that
Windstar to slide out. In short, it's not worth the risk of getting in an accident by driving around on worn-out tires.
Sure, you may not notice it if you mostly drive on dry roads, but when the rain comes and you're sliding all over the place,
you're gonna wish you replaced those baloney skins.
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