An Argument We Were Having....

[InnocenceLost57]

Soooo my dad and my dance teacher and my other dance teacher and I were all arguing about cruise control in cars. bizarre, I know, but hey, we're all strange. But Mary and I were of the opinion that the cruise control can apply the brakes to slow you down to the speed you've set it at, while my dad and Alan say it just eases off the gas. I know I'm probably wrong, but does anyone here know for sure? None of us have a clue about cars, of course....haha. But are there any mechanics on here? Anyone who has any idea about car stuff whatsoever? Man we're all clueless....

[OverDrive]

Unfortunately you are incorrect



it does ease off the gas, and does not apply the braking system at all. Actually, applying the breaking system, even for a slight second will automatically turn off cruise control.



If you are driving down a steep hill on cruise, it may use a different type of breaking method called gear breaking, in which it may switch down into 3rd gear, creating higher revolutions on the cylinders of the engine and slow you down a bit to keep to the speed cruise is set to, but it all depends on the car and the engineering of it. My dad's Accura has tip-tronic transmission - which means automatic and a semi-manual transmission. While in drive, he can switch to semi-manual (aka without a clutch) and can gear up or down and the car is smart enough not to gear down too far if it's going too fast, and it wont gear up if the engine is not reving enough. On this type of car, the engineering is there for gear breaking (which i've used manually on his car) but i've never experienced it (or had the opportunity in his car to experience it) while on cruise control.



If you gear break on a car that is not meant for it (check with your manufacturer of the car and do some online reasearch) you could fuck up your transmission (which is what I did in my old 1994 Dodge caravan before i traded it in for my 2005 Honda Civic)

[InnocenceLost57]

Hm. Wrong yet again about cars...what a surprise. Haha.



So Mary and I owe alan and my dad a cup of coffee each....how unfortunate.



So in some cars where you can tap buttons to accellerate or slow down while still remaining on cruise control, it's still just letting up on the gas? o.O



As I said before, I have no knowledge of cars whatsoever...not een how to drive very well. Haha. Go me....

[OverDrive]

Yep. Those buttons come on all cars with cruise control.. there are 3 buttons



Set/Decelerate

Resume/Accelerate

Cancel



So pressing Set/Decelerate when already on cruise will just tell the computer to go from 50 to 48 (lets say) and then to adjust that speed, the computer will not accelerate anymore and the car will slow down due to the laws of physics where energy is lost due to friction of the tires and the road.

[InnocenceLost57]

Ah. I understand....it's so nice to have smart people around to explain these things.



Thanks!

[OverDrive]

http://auto.howstuffworks.com/cruise-control.htm - all you wanted to know of how it works

[four]

Actually it depends on the car. I know with mine (from reading the manual) it can apply up to 30% of the braking power. So you all are right and wrong.

[InnocenceLost57]

Actually we were just yesterday getting in the same argument again and were discussing going downhill. My mom argued that it would have to apply the brakes at least some of the time to keep a constant speed while going down an incline over long periods of time. So would that have anything to do with it or make any difference at all?

[four]

Depending on the grade of the hill, your speed, and the natural resistance of your tires it might be able to just let off the accelerator, however many cars also will apply the brakes.