High Performance Lubricants: SAE 40 Passenger Car Engine Oil

[Hohn]

Post in thread 'HPL SAE 40 PCMO'

Mar 23, 2026

The VOA of the SAE 40 is ready.

Nothing really jumps out other than the trace aluminum that was mentioned earlier that is residue from the catalyst. The Mg/Ca ratio and levels are essentially identical to the 15w-40, as are Zn and P levels. The 10ppm silicon from the antifoam package is pretty typical of the HPL PCMOs.

Perhaps the virgin oxidation is slightly higher as a result of the extra esters used to thicken the GTL up a bit. I think that in general the heavier grade PCMO line gets more AN and less ester so they seem to run lower on virgin oxidation vs the low 30s...

• Hohn

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[fantastic]

Interested in how your auto handles the oil. Thanks for testing this HPL 40 Mono grade.

 

[buster]

You're probably right on the lower oxidation value due to more alkylated naphthalene. HPL's oils don't have the same high virgin oxidation level as RedLine, Amsoil Signature Series, Valvoline Premium Blue Restore or even their own HPL Engine Cleaner (110 virgin). This is likely due to the alkylated naphthalene cobase and specific ester type.

My guess is that high Mg level is what keeps the strong TBN retention. I've seen that characteristic in oils containing more Mg than Ca.

some good discussion via SonofJoe

Thread 'Detergents: Magnesium vs Calcium'

Sep 26, 2018

I read recently that magnesium is twice as effective as calcium as a detergent and is better at TBN retention. How true is that statement?

Also in terms of effectiveness, how does Boron play into the detergent picture?

• RDY4WAR
• Replies: 64
• Forum: Passenger Car Motor Oil (PCMO) - Gasoline Vehicles