Is grape juice ok to drink in an unopened can with the expiration date 5 years ago. It has also been refrigerated though unopened.
As long as the can is undamaged, and in good condition, it is safe. Expiration dates are typically used to define a period of time when the product is of the best quality, rather than to define safety. Since this was very likely a pasteurized product, it most certainly did not turn into wine or vinegar. It might not taste great, but if the can remained sealed it will not be unsafe either.
It might not kill you, but chances are it'll be vile. Why do this to yourself?
5 years is a long, long time.
At best it turned into wine (lol), at worse into vinegar!
I would discard it.