What are some good oil options for a 5.3L Vortec in a 2001 Yukon that has 160k. No valvetrain noise. It will be driven in Colorado Rockies only. Literally from airport downshifting and reving high all way up and down the mountains and back to the airport. Last year we drove it on 10-20 degree days up and down the moutains for approximately 1500 miles and then it used up 1 qt. I used a basic 5w30. This year I am thinking switching to a high mileage 5w40 from what I've read on here? The motor runs hard down shifting and living life in 3rd gear etc. Suggestions?