For the past 10 years the idea of 3k oci's have been drilled into my head. I want to take baby-steps into longer OCI's. Right now in my 2002 4cyl.GM sonoma I am using dino maxlife 5w30. However, I have heard lots of bad things about valvoline here ( "weak add pack") and want to know if dino maxlife can go to 4k miles. I did check the UOA's but most of them were SL or syn, so an accurate comparison isnt really possible. I do a mix of driving sometimes its all highway, others is 50/50 city/highway. The manual says to change the oil every 3-7.5k miles. So, what are your thoughts, opinions, theories, ect...Perhaps one day I will get up to 10k miles OCI, but for now Ill take babysteps. Thanks.