WINTER DRIVING
GEARSHIFT POSITION

WE NEED THIS! WHY WON'T AUTOMAKERS PROVIDE IT?

What is it?

It is a setting on an automatic transmission that leaves out all gears with a ratio higher than 1.60:1. This keeps the wheels from spinning when in the car is on a low-traction surface such as ice or snow. It was available in several different forms over the years:

Most other brands do not have this feature.

Note that the "2" position on other makes (especially GM and Chrysler) provides a selection that shifts between first and second gear. Some GM cars have "S" instead of "2."

Why is it needed?

In winter driving, the standard operation of an automatic transmission often causes the wheels to spin, because the transmission automatically provides the maximum amount of torque it can. The driver does not normally have any way to limit torque, other than by backing off the throttle.

The problem is that sometimes enough power is needed to go up a hill, but the torque must be limited because the surface is slippery. Without a winter driving position, the driver has no way to control torque without also throttling back.

Does it work?

The page author has in the past owned two different cars with this feature. The reason he can not buy one now is that the Cash for Clunkers program removed most of the cars with this feature from the used car market. So he modified a car (see "Build your own" at the bottom of this page). The feature has gotten him through conditions that could cause a wreck with an ordinary car.

Many others swear by this feature. It has gotten many people out of conditions where they would have otherwise been stuck, off the road, or in a crash. And the purpose of the feature is in the owner manuals of the cars that have it.

What is an example of how well it works?

There was a sudden ice storm in the page author's hometown in 2003. The author had just bought a used 1995 Ford Windstar 3 months earlier. He was leaving a shopping mall, and was confronted with a scene of cars sliding off the road everywhere in front of him. There were more cars in the ditch and on the grass than there were on the road. This was on a flat road. The page author put his gearshift in the "2" position. With that, and the antilock brakes, the author had full control of his van.

The road then went up a steep hill which was the only way to get out of that area. While most of the other cars were spinning their wheels trying to get up the hill, the author was able to drive up the hill normally. He had no wheel spinning, no fishtailing, no loss of control. Several other drivers ended up off the road.

At the top of the hill, the author turned off of this main road, not because of any handling problems, but because he was concerned that other cars would crash into his. He drove on less-used roads to avoid most other cars until he arrived home.

Are there other methods?

There are systems called "Traction Control" which many makes started using instead of the Winter Driving function. There is also a differential that can lock up when a wheel is spinning.

What is the Problem?

With the advent of smaller engines and 6 or 8 speed transmissions, nobody is now providing a winter driving function. Many of the new transmissions have manual shifting features. But none of them allow the car to start moving in a gear with a gear reduction ratio less than 1.60:1.

What do automakers provide?

They are using traction control. But it does not work as well, because traction control acts only after wheel spin has already begun. Also, when more power is needed to climb a hill, the traction control gives up, and turns itself off.

How do the different methods work?

WINTER DRIVING POSITION TRACTION CONTROL LIMITED SLIP DIFFERENTIAL
The Winter driving position keeps the transmission from downshifting to any gear with a ratio larger than 1.60:1 This makes the slipping occur in the torque converter, rather than at the road wheels. It prevents wheel spin when used carefully. This transfers power to the other wheel on the axle. Traction control applies the brake to stop a wheel that has already started to spin. The brakes pulse, similar to the effect of antilock brakes. The limited slip differential locks the two wheels on an axle together under icy conditions. Both wheels would have to lose traction before the car has a loss of control.

How do the different methods compare?


WINTER DRIVING POSITION TRACTION CONTROL LIMITED SLIP DIFFERENTIAL
A
D
V
A
N
T
A
G
E
S
  1. Does not try to move the car in first gear, preventing wheel spin before it happens.
  2. Because wheel spin does not happen, the ice is not made slicker.
  3. Works even on hills.
  4. When it is the "2" position on the gearshift, it also assists with braking on ice.
  1. Works well when one side of the road is icy and the other side is clear.
  2. Works best on level ground.
  1. Works well when one side of the road is icy and the other side is clear.
  2. Works best on level ground.
  3. Works best on straight roads.
  4. Is always active, unless the car is making a turn.
D
I
S
A
D
V
A
N
T
A
G
E
S
  1. Requires the driver to activate it when needed.
  2. Requires some parts of the transmission to be made stronger than they would otherwise need to be.
  3. The driver may forget to turn it off, making the transmission run hotter.
  4. Requires better transmission cooling.
  5. This is not a panacea. It still requires careful driving.
  1. Tries to move the car in first gear, causing wheel spin.
  2. Gives up and turns itself off if both wheels on the drive axle are slipping at the same time.
  3. Does not work when trying to go uphill. Turns itself off or locks the brakes.
  4. Activates only after wheel spin has started. This means the spinning has already made the ice slicker.
  5. This is not a panacea. It still requires careful driving.
  1. Tries to move the car in first gear, causing wheel spin.
  2. Does not work well if the road is uniformly icy.
  3. Does not work well going uphill.
  4. The system is partially disabled when the car is turning or is on a curve.
  5. This is not a panacea. It still requires careful driving.

What if all three of these features are installed on the same car?


WINTER DRIVING POSITION, TRACTION CONTROL, and LIMITED SLIP DIFFERENTIAL
A
D
V
A
N
T
A
G
E
S
  1. Does not try to move the car in first gear, preventing wheel spin before it happens.
  2. Because wheel spin does not happen, the ice is not made slicker.
  3. Works even on hills. But traction control may have to be turned off.
  4. The gearshift does not have to be moved with the Second Gear Start or "D2" position. But normal driving should be selected when road conditions are not slippery.
  5. When it is the "2" position on the gearshift, it also assists with braking on ice.
  6. Shifting into a lower gear position with other methods also assists with braking on ice.
  7. Limited slip is always active, unless the car is making a turn.
D
I
S
A
D
V
A
N
T
A
G
E
S
  1. The Winter Driving position requires the driver to activate it when needed.
  2. Requires some parts of the transmission to be made stronger than they would otherwise need to be.
  3. Requires better transmission cooling.
  4. Traction control can lock the brakes when unable to regain traction. An indicator light may show when this happens. Traction control should be turned off to stop the brakes from locking.
  5. The driver may forget to turn off the Winter Driving position, making the transmission run hotter.
  6. If the Winter Driving control is the "2" position on the gearshift, the driver must shift back and forth between "2" and "D" with road speed and conditions.
  7. This is not a panacea. It still requires careful driving.

How expensive is a winter driving position to add to a design?

All it requires is either an electrical switch or another gearshift position, and some software changes in the computer controlling the drive train. Only if the design is already inadequate would some parts need to be strengthened and would the cooling system need to be improved.

In the case of the 6-speed or 8-speed transmissions with manual shift capability, change the software to allow starting to move the car in a high enough gear (ratio less than 1.60:1).

Are there any drawbacks to a winter driving position?

Some idiots use it for drag racing and damage the transmission. But racing voids the warranty of the entire car.

The driver may forget to turn it off, making the transmission run hotter.

Why won't automakers provide this valuable tool?

This is a mystery. It might be one or more of the following reasons.

What can you do about it?

Try the following:

Links