Which is the best oil?

Just use a name brand oil (not syn) that is rec for that engine and change oil often, I change my oil every 10,000 to 12,000 miles.

 

Use Mobil Delvac 15W40. I believe its the oil Detroit recommends, plus they rebottle it with their own label. It's also low priced at Wal Mart. This is the same oil I use in my 4 cylinder Saturn. Work's great.

 

I have always used Mobil Delvac and changed my oil at 20k-25k miles with samples ALWAYS taken. So far so good and 850k miles

 

Aussie Dave is spot on. Just select a name brand oil that is the best value and run it. All the major oils are good. True, that some engines have a slight preference one way or the other regarding a brand, but you will not know that without doing a good oil analysis program and tracking results. You should do that anyway. Very inexpensive to run a sample at each oil change and know what is going on inside that engine. I would just follow the engine manufacturers recommended drain intervals at first. If the oil isn't holding up to that, then back off a little. Your oil sample test will show if it isn't. Most major oils will do fantastic way beyond 15-20000 miles. No use throwing more money down the maintenance hole than you have too.

To your original point, fr8wurx, I have a 12.7 Series 60 pre-egr that I have excellent oil samples using Delo. Another interesting brand that has shown very good numbers is the Mystik JT-8 engine oil. It is usually sold at Farm and Home type of stores. That is a sleeper of an oil, in that it rivals the quality of the normal name brands and can be had, usually, much cheaper. Same can be said of the Kendall engine oils. I took a Cummins N-14 to 1.4 million on Kendall oil doing 30,000 mile oil changes and never had an engine problem.

This is why I state, find a good oil at the best value you can. And follow good maintenance procedures. There is NO one best oil. The only thing one could possibly do in regard to what you are doing is maybe the type of oil filters you get and maybe using a bypass or centrifuge for additional filtration. That would do more for you than any one brand of oil, as keeping the oil cleaner will do more to protect your engine than some boutique engine oil. I like the results from Donaldson Extended Life oil filters on my Series 60. I am also using a bypass filter. Oil samples come out really good. At the shop I frequent for my oil changes, the Donaldson Extended Life are the same price as the regular Donaldsons. No brainer. Yet the extended life version offers a synthetic matrix filter media compared to paper. It will filter finer than the standard version filter yet offers a slightly better flow rate. Good value in a filter.

 

Why not syn?

 

I have used Rotella T all of my trucking life. Just be sure the weight and SAE fits what the engine requires.

Ive carried enough gallons to endure a loss of several gallons if the oil cap blew off or something else leaked too much as happened a couple of times. Pricing is of no concern. Its a bottle of gallon Rotella. Dump it in there. The higher level thinking goes to the shop people. I am just a "Drivah"

 

Haha thank you sir, I’m using delo 15w40 synblend it’s about $16-17 at Walmart.

 

Check out Schaefer. They claim a high detergency package in their oil that will clean up a dirty motor. I’m running the Ultra Performance 10w30 right now and in 60k miles I’ll see inside when I do my overhead. Most engine oils are great these days. The only real difference is how powerful is the detergency. Schaefer, Royal Purple, Delo, Valvoline Premium Blue, and Total are the oils that I feel have the highest detergency. It’s hard to gather that from their data sheets. I go by oil samples I’ve seen posted and there are YouTube videos out there as well.
Delo has a new oil coming out this month called Delo 600. I’d lie to check that one out..