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Weight in trunk?

My mother is concerned for my safety and believes that by placing weight in the trunk I will have more control over my car in the wintry weather. In a rear-wheel drive car I would believe she would be correct, however, my car is front-wheel driven. I would venture to guess that by placing weight in the trunk I am shifting the cars center of gravity toward the back and giving less control to my driving wheels. Can someone clarify?


  • edited November 2008
    You're right. She's got the traditional rear-wheel-drive vehicle in mind.
  • edited November 2008
    Remember that adding weight anywhere on a car will not only give you more traction on the wheels where the weight is added, but also more weight for the tyres to try and stop or keep from skidding. That weight on a RWD car might make it less likely to get stuck and might make it more likely to loose control.

    Get your mother a set of four winter tyres with wheels so she can be safer FWD or RWD. They will also help keep the car on the road and to stop better. They would make a great early Christmas present.
  • edited November 2008
    It's not his mother he's worried about, his mom is worried about him. And no, you do not need any weight in a front wheel drive car. I have owned many, and they don't need it. The engine supplies the weight. It will go fine in the snow and the back will follow right along. Tell your mom not to worry, it will be fine.
  • edited November 2008

    If this was a RWD car, your mother would be correct, as long as the weight was placed directly over the rear axle. Placing the weight in the extreme rear of the trunk would actually produce a "pendulum effect" on a slippery surface.

    That being said, a FWD car has no need for weight in the trunk, and in fact, this would disturb the normal weight distribution and actually lessen front wheel traction. As Mr. Meehan stated, the best bet for improved snow and ice traction in any vehicle is a set of 4 modern winter tires.
  • edited November 2008 addition, consider that added weight in the trunk of a FWD has a negative effect when going up hill in slippery conditions. This happens when the the center of gravity shifts rearward, making it more difficult to retain traction. When FWD looses traction, you also loose steerage. In a RWD the rearward shift aids traction with minimal effect on steering.
    Bottom slippery conditions, keep unnecessary weight OUT of the trunk in FWD, esp. in hilly terrain. Also..a FWD has better traction going up hill in reverse. Keep that in mind when parking in a sloped driveway in slippery conditions.

    After all....any vehicle that depends upon ultimate traction (tractors, race cars, police cruisers, other emergency vehicles etc.) have a vast majority of RWD or 4wd. For a good reason.
  • edited November 2008
    Control is lost in a RWD car when weight is insufficient to retain traction. Adding weight in the trunk to a RWD, forward of the rear wheels, is more often an aid to traction than a deterrent.
  • edited November 2008
    is more often an aid

    Possible, but the point I was trying to make is that no one should make the assumption that it will help. It may or it may make things worse. It may be a general rule butt it is not a universal rule.

    Good Winter tyres is a universal rule.

  • edited November 2008
    Although this idea was invented for RWD cars and trucks, your FWD car might benefit as well. Even with FWD, take a look at what happens if you lose traction. If you lose traction with the front wheels, you can steer them in the direction of the skid. However, the rear wheels can't be turned in the same way. They must retain or regain traction without pivoting individually. So as long as it doesn't take any weight off the front, there might be a benefit.

    Increasing traction of the rear wheels in winter weather is always a good idea, regardless of which wheels push the car. When you try to stop on a slick surface, the more traction you have the better off you will be.

    A RWD vehicle is pretty well balanced from front to rear. A FWD car will have even less weight in the back than a RWD car. Therefore, in my opinion, a FWD car might actually see more benefit that a RWD car.
  • edited December 2008
    "If you lose traction with the front wheels, you can steer them in the direction of the skid."

    That is a "dangerous" statement to make. Assuming you have traction control, is the only time you retain steerage in slippery condition with some traction loss in FWD. You may be able to steer a FWD in the direction of a skid....but nothing will happen. As long as the FWD wheels have no traction, you will plow straight ahead. The only exception in very deep snow with a slight "skiing" affect may induce some turning. I've raced FWD, RWD and AWD on ice.....and FWD is only effectively better if it's part of the old "free wheeling" drive of the early two stroke SAABs. Modern awd and balanced rwd is ALWAYS better.

    In RWD, when the rear spinning wheels loose traction, and the car fish tails, it will still tend to follow the front non powered steering wheels wheels which retain traction.

    Going down a steep very slippery road (ice covered) it is best to place car in neutral and retain steerage with FWD, using the brakes with abs to control speed.

    Generally, FWD may be more forgiving for inexperienced drivers in slippery conditions at lower speeds because of the initial weight bias. The problem arises when speeds increase, and FWD is LESS forgiving than rwd. In experienced hands, balanced rwd is always superior in just about every condition to FWD.

    Any "cops" out there that are in a high speed chase with any thing but a well suspended/tired/powered rwd car are at a huge, unsafe disadvantage to any one that is.
  • edited December 2008
    "If you lose traction with the front wheels, you can steer them in the direction of the skid."

    How is that dangerous? Isn't that what they tell every driver to do in basic driver's education?

    What does traction control have to do with it? I thought traction control only kicked in while accelerating when the tires spin from a lack of traction. Why would anyone in a skid accelerate? I am talking about steering out of a skid while coasting in gear. Could you be thinking about automatic stability management?
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