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?
I use mine on “normal” wet roads, but do not use it in low traction conditions (including deep water on the road surface).
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.
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.)
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.
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.
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.
Very well expressed, Josh!
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.
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.
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.
Did the email you got mention cars leaping off the road and flying through the air? Just wondering. I always love to hear that description, even though it’s total fantasy. Imagine, cars leaping off the road because the cruise was on in the rain. Vehicles weighing nearly two tons JUMPING into the air because they hydroplaned for a second or two. COOL!
If that’s all it takes to fly in a car, count me in.
Use the cruise control when conditions warrant. Don’t use it when conditions are unsafe, due to heavy traffic or adverse weather. Simple!
The important distinction is whether or not there is any collected or standing water on the road. Compared to asphalt, concrete is virtually nonporous. So I turn off the cruise control when driving on wet concrete, when driving on asphalt where the water has collected visibly, and when it is raining on either surface.
Moisture alone will not make you hydroplane. Collected water, even a fraction of an inch, can lead to hydroplaning.
I guess you have never seen a car spin out of control from hydroplaning. It isn’t dramatic as flying though the air, but it will land you in a ditch before you realize what happened. As a professional truck driver I have seen it happen a few times completely unexpected.
I’ve seen that goofball e-mail. What supposedly happens is the car will magically accelerate out of control, and maybe even become airborne. Apparently, the laws of physics have been repealed wherever this bit of sage advice was composed.
But using cruise control isn’t a good idea in slippery conditions when every split second of reaction time counts. Mountainbike put it well, as did some others
Don’t get me wrong, I wasn’t saying you were wrong, I was trying to emphasize your point.