Dear Tom and Ray:
I recently bought a Lincoln Town Car with an anti-lock braking system (ABS). I've always been told to gently pump the brake pedal when stopping on icy or slippery surfaces. Should I abandon this practice and let the ABS take over, or just continue the old way? - David
TOM: Abandon it, David! Like you, we were taught to pump the brakes during a panic stop to keep the wheels from locking up and sending the car into a skid.
RAY: But that's exactly what ABS does automatically. In an emergency stop, you just plant your foot as hard as you can on the brake pedal, and the ABS automatically "pumps" the brakes and keeps the wheels from locking up. And it does the job much more effectively than you could ever do it with your foot. In fact, it can pump the brakes many times per second, if need be.
TOM: It is hard to unlearn old habits. So when you get your first car with ABS, we suggest you get in some practice. Take your car out to a safe place (like a big, empty parking lot) next time it snows. And practice deploying the anti-lock brakes.
RAY: You'll hear a chattering sound and feel a pulsating sensation in the brake pedal when the ABS is engaged. But don't be alarmed. Just keep your foot right there on the pedal.
TOM: You'll also notice that while your foot is slammed on the brake, you're still able to steer the car in the snow. That is the real advantage of anti-lock brakes. They don't really help you stop any faster, so you still have to drive slowly and leave plenty of room to stop. But they do let you keep steering the car while you make an emergency stop.
RAY: That's a point worth emphasizing. Don't get cocky and drive like a nut just because you have ABS. It won't stop you from going off the side of a cliff. It'll just allow you to steer in an emergency stop, so you can steer away from a bridge abutment, and steer into something soft - like a roadside farm stand.
Dear Tom and Ray:
I have a clicking noise coming from the right rear wheel of my 1982 Datsun 200SX. This noise comes and goes, but it keeps getting worse and worse. The noise always stops when I apply the brake. My mechanic and Midas Muffler have both inspected my brakes and declared them OK. I think the problem may be a caliper. What do you think? - Paul
TOM: Well, you already have the problem three-quarters solved, Paul. You know that it's coming from the right rear wheel, and you know it goes away when you step on the brakes. So you've got two choices now. You can either remove the right rear wheel entirely and drive around without it, or you can start replacing some brake components.
RAY: I'd start with the brake hardware, Paul. If one of the pads were a little bit loose, it could be shifting around as the disc spins and hitting the caliper.
TOM: But the sound is more likely to be coming from a warped rotor. It may not be creating any real braking problems yet, but it may be warped enough to just nick the brake pad as it comes around.
RAY: And it may not be warped enough that you can feel a pulsing in the pedal when you apply the brake at high speeds, but if it's the rotor, you eventually will.
TOM: Ask your mechanic to look again. Have him change the brake hardware and put his dial indicator on that rotor. I'm sure he'll find the problem.