Originally Posted by Nuke
Although today's engines don't necessarily require break-in like they did 20-40 years ago, just drive with a little bit of caution but don't baby it. I'd vary the cruising speed and duration with a few... "spirited"... jaunts to 90 or 100 mph if you have the stomach (my 4.6L saw 130 for the first of many times in the first 600 miles). Do you think they roll off the assembly line and are tested by someone's grandmother?
every car comes off of end-of-line and goes over to the rolls (chassis dyno.) After a diagnostic check it goes up on the rollers and the tech runs it up to an indicated 60 mph and coasts down, then gets another diagnostic check. I can assure you they don't do that gently.