I have a Subaru Forrester 2007 and the cruise control will not slow the car down at all and my old forrester did. Called Subaru and they said well that is true the newer models do not behave the way the older ones did and YES you have to apply the brake on a down grade to slow it down. Seems crazy to call this option “cruise control” more like “accelerate only”. Subaru cant explain why they did this change and its not documented anywhere. Seems like a real bad thing they have done.
Sounds like Subaru (and others) are trying to protect themselves from potential Toytota UA like lawsuits. Want to go – hit the gas. Want to stop – hit the brakes. Simplicity reduces the chance for operator error (the actual cause of Toyota UA).
It all depends on the hill. Normally a cruse control will do nothing more than taking your foot off the accelerator while you are going down hill. I have not seen one that would apply brakes.
Most cruise controls work exactly this way (do not apply the brakes or down shift the transmission). Generally, only the higher end cars have cruise controls that do anything more than release the accelerator when going down hill.
Cruise control has been called cruise control for a very long time. For very many years none of them had the ability to do any braking or downshifting.