Benghazi coverage, the Bush National Guard story coverage, their NSA/Snowden fluff piece, etc. It's not hard to find credible criticism of 60 Minutes, even if you can't tell just by watching it.

http://www.cjr.org/behind_the_news/60_minutes_bad_run.php

Lara Logan was suspended from the show for months after airing her report, and the show issued an on air retraction and apology about that story after it broke that the main person they interviewed for the piece was lying.

But "entirely untrustworthy" is quite a stretch.

The first one that comes to mind was their fraudulent reporting about the audi 5000 and "sudden acceleration" in the 80s. Their lies almost destroyed an entire company.

http://en.wikipedia.org/wiki/Audi_100#Reported_sudden_uninte...

And before that, in 1980, a hatchet job on the Jeep, must have been the CJ-7 both because of the date and how difficult it was for them to roll it, even using robot drivers that manipulated the steering wheel twice as fast as a human can while gunning the engine.

There was plenty of less overt stuff in the '70s. Then you might mosey through this list, which only has the worst of the worst: https://en.wikipedia.org/wiki/60_Minutes#Controversies

Per that, it took 15 years for Audi sales to recover.

It would be interesting to see if anyone associated with the show has made money of this - surely if you know, a week or two before it airs, of a piece that's going to destroy the reputation of a company then you can trade on that to great effect.