Not started an "Oil War". Simply passing on information for your enjoyment. I use standard Valvoline diesel dino oil, 15W-40. If you watch the sales you can usually get it at a good price and stock up. I use a good filter from Genos.

And - because the engine has flat tappets - I add two bottles of Comp Cams break in additive with every oil change. That brings the zinc up where it's supposed to be to protect the engine.

I was going to run this batch of oil to 15K. But I was getting ready for one long trip and a bunch of short ones, so I changed it early at 12K.

This proves that for my truck, changing the oil every 5K miles is a true waste of money, time, and effort. It also indicates that spending extra money on synthetic and semi-synthetic oils is also a waste of money.

Your mileage may vary.



BTW, it's on sale right now at Autozone for $14 a gallon. Not a great price, but if you need some right now you could save a few bux.

 

The biggest is any engine mods, following your oil filter. BTW, if you live where it gets down to below 0 in the winter, synthetic oil is about the only thing you can run w/o having an oil pan heater.

 

I have come to the same conclusion for my truck after running OAs on several 15w40 oils. More people should do them and take the mystery out of oil changes.

 

Wow that oil got thick... 17.54 and the previous change was 19+ cST. Yikes, that is 50wt oil by the time you change it but that might be from the additive.

 

I'm running the same oil and the Amsoil bypass filter set up and change mine every 8k with the bypass filter every 16k miles. My last OA was great and I will do another with my next change and if it still looks great I will probably go to 10k mile changes.

I agree with Shorts too. If more people did the OA they would be shocked at the results and it would easily reduce the "My XXXX oil is the best because......." discussions!

 

I have never run a bypass filter. But I have heard they increase oil life by up to 50%???? If you're changing at 8K, I'd almost bet you don't need to. Of course, it all depends on the use of a the vehicle. Mine doesn't get beat on hard at all.

UOA's are very helpfull, IMO. That's why I pay the $35 to do them. It's hard to argue with facts and data - although many people try. Especially when it comes to motor oil. Or global warming. Oops! Did I say that out loud?

 

They "Claim" you can go 15k on the interval and 30k on the bypass filter but with the amount of soot these build up I will not go over 10k and 20k on bypass even though the UOA might say I can. If the next few samples keep saying I can I "Might" go 12k and 24k.