Has the upper limit on Presidential candidate ages been hit?

[MarkD]

We have had two Supreme Court Justices retire from the office at age 90, and a Chief Justice who died in office at age 87. Representative John Dingell, Jr. retired from the House at age 88, and Senator Carl Hayden retired at the age of 91.

So I think there will be nothing wrong with Joe Biden running for re-election when he's 81-going-on-82, and serving for two whole terms, surviving in office until he retires at age 86.