Flipping a tire is often less about lifting and more about pushing.
Comparing the movement to a hitting a blocking sled on a football field, Kurtis Bowler of Rainier CrossFit says it’s important to push through the tire, driving it up and over rather than just picking it up.
The movement still has some of the characteristics of a deadlift, but Bowler recommends having the feet behind your hips and using a grip width that’s close to what you might use for a snatch. After the tire is up, you can drive one leg into it to finish the flip, or you can use a movement similar to a clean to pop the tire up a bit while you drop under. Bowler doesn’t recommend the latter because it puts a great deal of strain on one Achilles tendon while the other is mostly unloaded.
The most important part, of course, is making sure all roaming kiddies are out of the way before pushing a big tire over.
Additional reading: It’s in the Bag by Josh Henkin, published July 2, 2009.