"clicking" from any specific side of the front of the car could be a CV joint, but you would notice any noise it makes will usually get louder and more frequent as you turn the wheel further while in motion.
this sliding sound isnt a very detailed despription, im sure i am not the only confused reader(i have no clue what a "sliding" cog wheel sounds or feels like)...
Are you saying that it feels like gear teeth(cogs) are slipping? or is it a sound? is it a slow noise or feeling, or fast, and does it increase with speed?
stuff like that is very helpfull
good luck