Shell Rotella T6 Oil

[454cid]

Rotella T6 5w-40 is currently 1,150 ppm phosphorous (http://www.pqiamerica.com/June%202014/s ... ellat6.htm), higher than the recommended passenger car standard of 800 ppm maximum.

What was the maximum phosphorous level recommend during the P80 years?

[erikv11]

All I can say is a firm "I don't know." Full history of oil chemistries seems too much of a black hole for me.

But previously (e.g. in 2017, see link above from foggydogg) Rotella T6 in xx-40W was under 1,000 ppm, so it didn't really matter for this oil. Shell changed the formulation recently, I don't know when that happened, so that it is now a higher P level, above 1,000.

FWIW, I'd be more inclined to trust later, more recent recommendations on chemistry, and the earlier, manufacturer recommendations on viscosity.

[MoVolvos]

4 quarts of the Shell vs 5 quarts of Mobil One at Wallymart for essentially the same price. Wonder if it's worth the difference.

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I have such a large fleet of various make and models with a wide range of mileage not to mentions year of trying different oils. Tried Mobil 1 synthetic in the mid 90's when my Pepboys Service Manager introduced me to it whereas Rotella was about 10 years ago.

The Mobil 1 has always felt like water in the engine. Cars don't have power and WOT's make the lower end groan as if lost lubrication so have not used for many years. With the Rotella the cars are smooth and engine runs robust. Tried the Mobil 1 when Costco sold it cheap and purchased the Mobil Delvac Dino 15W40 within the last two years or so. The Mobil 1 is still like water and the Dino Delvac stopped the ticking or oil cavitation in the pan of the P80. Was pretty impressed with the 15W40 Delvac.

Pricing is not the most important factor when comparing the two.
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