Should the cruise control function on a '98 Gs300 have the ability to automatically apply the brakes or change down a gear when travelling down steep gradients thereby maintaining the preset speed. Currently mine will allow the car to exceed the set limit. The system works fine on the flat and up hills but not down them.

[quote name='Summerbj' post='695881' date='Oct 27 2009, 11:30 PM']Should the cruise control function on a '98 Gs300 have the ability to automatically apply the brakes or change down a gear when travelling down steep gradients thereby maintaining the preset speed. Currently mine will allow the car to exceed the set limit. The system works fine on the flat and up hills but not down them.[/quote]

Hi,I take it that your not used to dirving autos with cruise control, I have been driving them for many many years I love them.
Cruise control are resigned for long straight roads (bends hills and are not), and answer to your questions are no it dont apply the brakes if you are going down a sleep hill it is designed to reduce the fuel and change gear which dos feel like the brakes are appied at times and speed will go up just a bit.
I have always knocked mine off on hills and bends unless it the odd one.
Hope this helps