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Cruise Control on Wet Roads?

Has anyone gotten the email that says NEVER use your cruise control on wet roads?

It claims you'll be in big trouble if you hydroplane. I don't use mine in hazardous conditions, but I do on occasion when the road is wet. Even if I do hydroplane, I pay enough attention that I'd just tap the brake and react accordingly.

What do y'll think?
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Comments

  • edited January 2008
    I use mine on "normal" wet roads, but do not use it in low traction conditions (including deep water on the road surface).
  • edited January 2008
    Don't try to defend this when the person is a know-it-all and isn't going to agree with anything that isn't written in a newspaper or said on the news. I use cruise control on wet roads where I have driven before when I know there aren't deep puddles or hydroplaning conditions. I also have used it in all other conditions at lower speeds. If you have old tires that never were any good, I would say to never use cruise control on any wet roads. Of course, if the cruise control is an old one, it can go crazy on you but chances are good that you won't have a disaster anyway. The only valid point here is that people with good judgement usually don't cause bad things to happen. Even my awful judgment didn't kill me before I chose to pretend to be smart. I'm assuming that we don't do 79 MPH on cruise control on a curvy highway every time it rains. Those who do can make headlines and jump up saying that they didn't know about the danger. I can do what I want with my good decisions and almost nothing with my bad ones.
  • edited January 2008
    This would be an excellent opportunity to open your Owner's Manual and read what it says on the topic. I would be more likely to trust something that I read in the Owner's Manual than something that came in a spam e-mail.

    (Hint--The Owner's Manual also advises against using the cruise control in wet conditions, but you should read the text anyway.)
  • edited January 2008
    Your cruise control uses data from the Vehicle Speed Sensor to decide how fast you're going. The VSS is usually hooked up to the speedometer which is usually driven from the output shaft of the transmission. To keep it simple say it's a RWD car-- the speedometer really measures the speed of the driveshaft before the power is sent to the differential and distributed to the wheels. Now, it is possible in deep water or other slippery conditions that if one tire loses traction but the other one doesn't, that the speed being measured by the VSS will go down and the cruise control will respond by giving the engine more throttle, which will lead to a spectacular spin, and possibly a fiery crash.

    The above scenario isn't too likely, however, because it's far more likely that if a wheel loses traction, the driveshaft will speed up and the cruise control will let off on the throttle. So you're generally okay on "normal" wet roads like Craig says, but it's probably not a great idea to be using cruise control on really bad roads.
  • edited January 2008
    When there's a risk of losing traction, including areas that may have puddles, I leave the cruise control off. In normal wet weather in the summer on newer roads that have good runoff AND where the speeds are modest I may use it. Sometimes.

    Always err on the side of safety. Not having it engaged allows you to reduce your speed gradually by lifting your foot off the gas. Having it enegaged means you need to either take the extra second to disengage it or use the brakes. A second when you're losing traction can be enough to make the difference between a safe ride and a crash.
  • edited January 2008
    I think "when there's a risk of losing traction" is the key to this whole issue. I agree with the original poster that using the cruise on wet roads isn't inherently dangerous, but I disagree that if you start hydroplaning, you will have the presence of mind to tap the brake, apply the correct amount of throttle, apply the correct steering inputs, and save the car, all in the 1/4 of a second it takes for your car to start getting sideways. I don't know if you've ever been in the situation, but let me tell you, it's a lot harder to save a car that's already going sideways, than it is to prevent it from going sideways in the first place. Momentum and inertia are funny things like that.
  • edited January 2008
  • edited January 2008
    I thought I said that. I advocated not using cruise because the amount of time it takes to perform those actions could be too long and you could end up out of control.

    Yup, I've been in a slide. That's what caused me to say to always err on the side of safety and don't use cruise when there's a risk of losing traction.
  • edited January 2008
    I agree with "don't use cruise when there's a risk of losing traction." However, IMHO that does not include driving in "normal" rain or wet weather.
  • edited January 2008
    Very well said Josh. I was going to say something along those lines, but I can't top yours.

    Anytime the conditions would suggest the possibility, I shut off cruse. It really is not all that bad.
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