I have a 4 1/2 year old right now who is showing no sign of slowing down (even though she is missing a back leg). Also, at 3 1/2, she had her first and only baby.
When I was in Baton Rouge, LA, the oldest chinchilla that my vet had seen was 16 years old. Later, I hired a pet sitter who had a chinchilla who was also 16 (not the same chin- the first chin passed away in 2000). While her coat wasn't the best, the chinchilla still had lots of energy. She loved her wheel and was pretty cranky. Both the 16 years old were female, but Chapman had a male live to be 22+, so its probably not a gender thing.