Engine oil

[AirTool]

I would love to hear an explanation of exactly how you propose to determine such a thing with absolute certainty.

That's the job of the person who posts the claim....and generally my point.

We are all in love with brands (including me) but the most important variable is actually CHANGING the oil - not so much the brand. Most brands don't even make their products anymore.

I had a friend that worked at Southwest Research Institute when I was in engineering school. They test many things there including fuels and lubricants. One thing he reported was that the consistent winner across the board were Mobil products. They were usually number 1 in the tests. If not, number 2. Which might be why PCM always recommended Mobil ATF for the tranny.

Mobil as we know it is gone. Texaco, Havoline, and others....gone.

It is generally best to pick a brand and stick with it to avoid components from each brand reacting with each other in a negative way - but even those issues are really gone.

[TRBenj]

On a newer, roller motor, I would agree. Pretty much any oil of the proper viscosity is going to be fine, assuming it is changed regularly. Especially the synthetics- I vary between Pennzoil and M1 on my truck... but wouldnt hesitate to buy Castrol or Valvoline if they were priced lower.

On a flat tappet motor, you need to be very careful to choose an oil with proper ingredients to avoid cam/lifter failures. While some people may scoff at the possibility of wiping out a cam, I can assure you that it can and does happen. And it sucks. There are many possible causes for such a failure, including lower quality metals used in either the cam or lifters, as well as sloppy manufacturing tolerances (made in China?)... but oil is a very easy thing that can be controlled. There is minimal additional cost associated with using a high quality, high zinc/phos oil that might just prevent a premature engine failure... so turning a blind eye and failing to use one of these oils is just silly and unnecessary. The hard work (identifying which ones are best and where to get them) has already been done by those of us who care about such things. Just my 2 cents.

[swc5150]

Ironically I was thinking just that! Intervals are key, not brands of oil. How many modern engine failures are really traced back to lubrication problems - unless the owner never changes the oil? I'm closing in on 225k mile on my Tahoe, and it runs perfect.