I'm sorry if i made a mistake...i just remember that on ios 6 and its earlier version OS i had always heard nothing when i dialed to make phone calls... So confused now,
You sure you didn't have the silent/mute on the side of your iPhone on because with it on it silents your notification sounds, ringtones and phone app dial sounds
The sound of keypad dial is connected to the ringer sound--if you have the ringer sound turned off (via the mute switch, for example) then there will be no dial sound either, and if you have the ringer sound turned on but set to the lowest setting for example, then you'll have a very low dial sound as well. This is how it has been before and how it still seems to be now.