Overdrive in icy conditions on Pontiac VIBE

#1

My daughter lives in VT and has a VIBE with winter tires. But in icy conditions she has had problems with not getting any traction on hills. We wondered about having the overdrive on–I read the discussion on the Matrix (which is the same car essentially)–but no one mentioned ice on hills as being a situation for turning off overdrive. Should it be on or off in icy, hilly situations and/or should she be in a lower gear? Family debate going on!

#2

It has been a long time since I last drive a car with automatic transmission.

What are the choices? Back when I did drive car’s with automatics (I have never owned one.) you had a snow setting. It would lock out low to reduce the problem you are talking about.

Also when does she have a problem? When starting from a dead stop, or keeping traction when climbing the hill? While trying to accelerate

#3

It really doesn’t matter unless you’re going over 45 MPH or so. All overdrive is a gear where the output shaft is turning slower than the engine. If anything it would be easier to drive in overdrive on hills because the reduced torque multiplication provided by the overdrive gearing would make it harder to spin the tires. At lower speeds overdrive has no bearing on how well your car drives in the snow since it’s not engaged.

#4

First, going up hill on ice is difficult for any car…but.

Surprisingly, the higher the gear, the less power for acceleration, the BETTER for going up hills on ice. Less chance of breaking traction and loosing steering. Because it’s an auto, you’ll not have control of a standard. IMO, it makes little difference.

If she encounters lots of hills and ice conditions, studs may be the next step.

Also, FWD LOOSES traction going up hills as the center of gravity shifts rearward. They are poor in these conditions. Things you can do to help…eliminate as much weight in the rear as you can before attempting the hill. Put passengers in front seat temporarily if short distance.

Another trick if just a short distance (driveway) is to back up the hill. They have excellent traction going up hills in reverse. Beware of the difference in steering control in reverse. If you can’t make the hill. at least you’re pointed in the right direction.

The best strategy that works well me for all cars going up slippery hills, is to accelerate and increase speed before you get to the hill and try to balance the loss of momentum, with the loss of traction you feel while going up by easing OFF the gas as you go. It takes practice, but with time you’d be surprised how steep a hill you can traverse in safety.

Regardless of what ever else you hear about FWD…they are terrible going up hill in slippery conditions. On ice ALL cars will be poor performers but FWD is worse in these conditions.

Remember on ice…change of speed and direction is bad, forward momentum is good. If that does not agree with your INTENDED direction and speed, you’re in trouble.

#5

“What are the choices? Back when I did drive car’s with automatics (I have never owned one.) you had a snow setting. It would lock out low to reduce the problem you are talking about.”

Exactly…locking out low reduces acceleration which causes the car to loose traction. You need to reduce power for acceleration to the wheels. With standards as you have …you have so much more control of drive train

#6

Thank you all for your comments–the real problem arose in traffic going up a hill when it came to a standstill. (This is an automatic drive car.) She could not get started (wheels spinning on ice) until some kind souls gave a push (fortunately the Vibe is small and relatively light–also unfortunate because there is not much weight on the front). So forward momentum certainly helped–she didn’t have any choice but to stop.

Our daughter lives on a steep hill with a dirt road and with a “running start” our rental car (Altima with all season tires) made it up OK. But if we had had to stop, I think we would have had to back down and start all over again!

Her previous car was a front wheel drive RAV4 with manual transmission and she thinks it was much better on snow and ice. I agree that the studs might be the next step. So the bottom line re overdrive is that it could help, so it doesn’t matter if it is on or off under the conditions described. Is that correct?

#7

That’s correct, OD only engages once you’re up to speed, will have no effect on starting up a hill.

#8

I want to try to expand on what FoDaddy said, simply because all too many people seem to be confused about what Overdrive is. As was said, Overdrive only comes into play at constant speeds above–here is where it varies from car to car–anywhere from 35 mph to 45 mph, and it designed to save gas by allowing the engine to turn over at a slower rate. It is sort of a super high gear for economical highway travel.

As was also said or implied, the higher the gear, the less torque is applied to the drive wheels, and less torque=less wheel spin. So, if anything, Overdrive would actually produce less wheel-spin than a lower gear at higher driving speeds.

One problem with the original post’s question is that the OP did not state at which speeds his daughter encounters wheel spin. But, in the absence of that necessary information, allow me to offer another suggestion.

On some makes of cars (Subaru and Honda come to mind), by placing the shift lever in 2nd gear, the driver effectively “locks out” first gear, and locking out first gear will markedly improve low-speed traction. If we are talking about a situation of the driver having problems with starting traction and low-speed traction on a hill, being able to lock out first gear is ideal–as long as the Toyota Matrix (and its Pontiac clone) transmission has this great feature.

How does one find out about this? By reading the Owner’s Manual! So, consult the manual in order to find out if this car’s transmission allows you to skip first gear. If it has this feature, just remember that this procedure also locks out 3rd gear and Overdrive, so when you reach the rpm limit for 2nd gear, it is necessary to upshift to the “normal” Drive position.

If that car’s transmission does not allow you to skip first gear, then all that can be done is to remember that the time to accelerate is BEFORE the hill, not on the hill. I can recall countless situations where people attempted to accelerate once they were on an upgrade, and wound up totally losing traction. Granted, this occurred with rear wheel drive cars which are essentially useless unless they have winter tires and are driven expertly, but all the same, your daughter should remember to accelerate prior to climbing the hill, and perhaps to lessen her pressure on the gas pedal a bit as the car climbs the hill in order to reduce torque a bit.

#9

I don’t believe the Vibe can skip first gear–as noted below, my daughter was stopped going up a hill on ice in a lane of traffic. So it was starting on ice on about a 30% grade. Probably hard to do under any circumstances. Short of getting a push to start going and accelerating slowly to reduce the torque. She probably should have gotten studded winter tires for this car.

Thanks for your comments (by the way I am her mother–).

#10

If your daughter is going to drive in these conditions, the real solution is to get a car with:

  1. Traction Control. It helps her accelerate in low traction conditions.
  2. Anti-lock Brakes. ABS will help her stop in low traction conditions.
  3. Automatic Stability Management. ASM will help her maintain a curve in low traction conditions.

Add these features to the winter tires, and she should be able to get from point A to point B in all but the worst weather.

#11

Good thoughts, but she just got this car, so not much chance that she will get another soon.

#12

Being a wagon, it does have more weight in the back with a lighter engine…and she should not not carry weight in the "trunk’ behind the rear seat. It’s time for studded snows…

Also a poor mans traction control when starting assuming it does have it…a very light application of the brake “sometimes” induces a little torque to the other wheel.
Normally all the power goes to the wheel with the least grip…not good if ones on ice. This I’ve tried many times with some good but mixed results.

I assume that she does not have studded tires. I highly recommend them for her situation.

#13

Just as a side note when I was young had a car with an auto trans and where when you put it into second it went into second, I thought since putting it into second helped avoid slipping on starts it would work for slowing down also, Take my word it does not work for slowing down your car on ice to force a downshift, I basically lost control of the car. 71 Chevy Nova.

#14

So right,any uncontrolled braking,esp. engine braking can make you loose traction.

#15

I had a '99 Chevy S-10 with antomatic and 4 wheel drive. I also drove a '01 S-10 204,000 miles. Each of the trucks could atart off in 2nd gear. Starting in 2nd gear and 4 wheel drive is a good setup.

#16

re: Studded snows

I’ve dealt with Vermont’s variously snowy, icy, sleety roads and washouts for years, and agree that a manual is a must, especially if you live on such a hill. I have owned studded snows–esp. when depending on back, dirt roads a lot. But I’ve heard a wide range of opinions about their usefulness on icy roads. Even w/studded snows, she should be very cautious, especially on dirt roads with more than a surface depth of ice. I’ve found studded tires don’t always provide an advantage.

#17

I found too that care must really be taken when new on dry roads…but on glare ice, they are excellent. I will say, the newest winter tires are getting very good at providing near stud ice traction w/o the disadvantages, the REAL expensive ones, Nokians example.

Aside…an old pair of dedicated hiking boots ? You can screw hex head sheet metal screws onto the perimeter…safely walk on any icy road for miles where the strap ons are a pain to keep tight.

#18

If I were driving in slippery conditiions, I would lock out the overdrive. I wouldn’t be driving very fast and therefore would not need overdrive. And you don’t need overdrive engaging and disengagine as you drive near the shifting point.

#19

I have never driven in Vermont but I have driven in Missouri for 60 years, manual and automatic and I definately prefer the auto. However if it is very slick and you are going downhill you might have to put the auto in neutral to avoid the rear wheels from pushing the vehicle. And the 2nd gear start up is a great help.

#20

For someone that lives in Missouri (and not NE), that’s very astute advice about putting the car in neutral in real slippery conditions…best way to maintain control with abs.