Gene K

The only Powertrain Engineer Ive ever heard weigh in it on it said "Dont worry about it. Drive like your going to use it".
The only thing that can cause issues in my opinion is constant low load and low rpm during break-in.
Even then with modern machining and materials most cars will still seat the rings.
Its not that easy to "glaze" a cylinder any more.

My own rule is no full throttle below 2,000 rpm or above 80% of max rpm for the first 50 miles. When ever i get a chance to I will let it slow to about 2000 rpm in a gear and rip it up to about 5000 rpm at 3/4 throttle and the let it decelerate with closed throttle back to 2000 rpm. I especially like to do this when I can accelerate uphill and decelerate down.

trane

I'm not quite sure why some people think that the factory says to baby the vehicle during break-in. I've read the break-in section of the 2010 manual and I presume the 2011 manual will be about the same. It says to avoid EXTENDED (emphasis mine) full-throttle applications for the first 1k. That doesn't mean driving like a granny for however long it takes you to get to 1k, it means don't drive WFO from 0 to the limiter in top gear.

The other aspect of break-in is a huge issue: don't loaf the motor along the highway with cruise engaged. Period. In fact, do yourself a favour and use Google maps or the like and choose routes avoiding highways/tolls till your 1k is done with. Make sure you're varying RPM and changing speed/load on the engine while driving. Doing this makes sure that wear is balanced at all RPM and the engine will run as smoothly as possible throughout the rev range.

After your 1k, change the oil using non-synth. Then carry on as you intend for the lifetime of the vehicle.

David Young

I think the 5.0L comes with full synthetic motor oil and the V-6 comes with a synthetic blend motor oil from the factory.