BG109 Engine Performance Restoration (11fl. oz)

How do you use this?

I noticed on my recent order of EPR that the date one the bottom of the can has expired- does it hurt the cleaning performance?

How do you know if you have heavy sludge in your engine? My valves look clean and I change my oil often. 176K miles on the truck

My car only have 56000 miles on it , can i use the 109 on my engine?