QUESTION: I was wondering what your thoughts were on ABS brakes when driving on icy roads? I live in a town with several streets on steep hills and when trying to stop or slow down when going down when they are covered with snow or ice there’s no stopping. All you get is the brake pedal pulsating several times a second. You just have to hope you stop before the stop sign. — Ron
Answer: In almost all road conditions, ABS brakes will outperform non-ABS brake systems for stopping, but, more important, vehicle stability. When stopping on any road surface, the maximum traction is achieved when the tire is still rotating and maintaining contact with the road surface. If you try to brake with maximum braking on a non-ABS system, some wheels will stop rotating and slide while others are still maintaining traction. This is even more pronounced on ice, where the sliding tire creates heat, which melts the ice and forms a water layer between the tire and the ice. Ice at the melting point or with water on it is very slippery! Just ask any curler why they sweep a rock and they will tell you the same thing.
With ABS braking, as soon as a tire starts to slide, the brake system releases the brake for that wheel until the tire begins to rotate again. Then it applies the brake again.
This happens several times a second, so close to maximum traction is obtained. Not only will it help you stop, it keeps the vehicle in control because all the tires have traction, not just one or two.
There are a couple situations where conventional brakes will outstop ABS brakes and these are in loose gravel or dirt and on sticky deep snow. In these cases, the stopped wheel acts like a plough and pushes a ridge of material before the tire, causing it to stop quicker. However, you do lose steering control.
ABS braking gives you the ability to brake and steer around an obstacle, although any time you steer you do extend the braking distance.
Finally, a good set of winter “ice” tires will help you stop on those steep icy hills. If you haven’t used them before, you will be amazed at the difference they make.
Question: I have searched the database and could not locate any information on applying sound deadening materials to vehicles to reduce road noise. I have a 2015 Honda CRV and find that there is a lot of road noise. Most of it comes from the tires — though there is quite a bit of wind noise, as well. I’ve read that some have found that applying sound-deadening products to the interior floor, doors and even the roof does a lot to quiet things down. It’s about $500 for the materials and I’m okay with spending a weekend doing the work. What experience do you have with this? — Al
Answer: The factory applies sound deadening to some panels, but in order to reduce vehicle weight and increase fuel economy, I have noticed that the amount of sound deadener in some vehicles has become much less in the past few years. There are several aftermarket sound deadeners used to quiet the interior and reduce heat transfer from the outside into the interior.
All are much better than the spray-on rubber undercoating commonly available. Automotive Audio shops also use it to create better sound in high-end aftermarket audio system installations. They can be a good resource for materials.
There are several brand names: Dynamat, Hushmat, B-quiet and Second Skin are but a few that use adhesive sheets with an aluminum backing. Peel the protector sheet off and stick the viscoelastic sheet to your body panel. The body panel should be clean of dirt, oil and rust. You can cut the sheet with scissors to fit odd shapes. The viscoelastic material absorbs the vibrations to keep the interior quiet.
There are also spray-on or paint-on coatings that do the same job. Check out Second Skin’s Spectrum lineup of spray on products. Not as easy to install but work well.
It will take a few hours and is not cheap to do a complete interior but it can make your car seem like a totally different vehicle.