I have a 2001 xterra. Truck has always used regular mobil 1 10w30 since 5k miles, now has 83,000, never burned oil. Oil changed at 5K intervals. Last change, at 80,000 miles, I used mobil 1 ep 10w30. Now, at 83,000 miles, I had to add half a quart.
I've read that when you switch to ep, sometime...