Ricktwuhk

I would recommend that you vary your speed, more specifically, vary the engine rpms during the trip. I do this whether towing or not towing on a long highway drive in that break-in period.

You can easily do this by locking out 6th gear for say 25 miles, then unlocking it, then locking it...

Ron AKA

The most important thing you can do for your engine, and especially the EcoBoost engine is seat the rings. That has to be done early -- within the first 500 miles before the cylinder walls start to glaze up. Once glazed you will never seat them any further. The EB has problems with gasoline getting by the rings and diluting the oil, so you want them to seat as well as possible. Here are a couple of articles on why and how you set the rings. The first is from an aircraft engine manufacturer, and does a good job of explaining why (see page 3). The second is from Hastings, a piston ring manufacturer and is more practical for a vehicle that isn't built to fly. Essentially you want to do about 10 full throttle runs from 30 mph to 60 mph, and you are done.

http://www.airpowerinc.com/downloads...FlightTips.pdf

http://www.hastingsmfg.com/ServiceTi..._procedure.htm

acadianbob

I was told that the reason for the 1,000 mile "rule" is that they want the rear axle differential to have time to "work in".