Is anything wrong with my tranny? When I put it in reverse I hear a clicking noise coming from the dash.

 

anyone know?

 

assuming your automatic, probably the shift cable snagging/rubbing/ hitting on something behind the dash. under the shift trim area

Other guess is that when you shift it to reverse, your engine will rock and might sometimes rub against something like a FSTB or other things making a pop or clunk/click noise.

 

It could be your shift lock clicking. You could pull the plastic cover off around the shifter and get easy access to it. It's on the lower right. If you have spilled any drinks in there that would might it stick. It's pretty easy to clean.