MY 2014 BUICK ENCORE makes a click sound when I step on the brake in park I never noticed this before with 40,000 miles on it , the SUV runs fine but the dealer says we have to diagnose it on the big computer in the shop and that is a cost of $115.00 . If any one knows this sound occurs sometimes when the car gets mileage on it but its perfectly normal to hear a click please let me know .

Sounds like the park solenoid releasing so you can take it out of park.

so its OK to drive and most of all why didnt I ever hear this clicking before 40K

Does it still do it when the shifter is in another gear?

no only park with ignition key on and then stepping on brake peddle,

Then its the shifter solenoid. Perfectly normal. Why you haven't heard it before, I don't know.

Agree. Many cars have some similar sound like this. Maybe the solenoid is more broken in than it was. Maybe there was some sound mitigation measure that was installed to quiet this sound and 40,000 miles later it is worn/flattened/gone/etc. I wouldn't worry about it. It will likely still work fine in the scrapyard after it has 250,000 miles and fifteen owners under its belt and has been made obsolete by flying cars and matter-energy transporters.

On a related subject: I suggest you run from any dealership that has to put something like this on "the big computer" to diagnose. This kind of thing is common knowledge for a dealership, and "the big computer" can't tell anything about the sound level of the brake-to-shift solenoid.