We use SAFTY KLEEN 5W30 at my work which is 100% recycled motor oil with no oil related problems at all, and only gripe I have is I can get MOBIL SUPER 5000 for 3.15 a qt, and NexGen is like $4.20 a qt, so not much of a value in my area. Didnt recall what the 5qt jug of nexgen was as wally world is usually out of it.