0W-16 oil as Lexus designates or 0W-20 full synthetic "Hybrid" as Mobil1 sells?

Suspecthathe tires do not heat much because they flex less being above the vehicle’s recommended 35 psi tire pressure.
Returning to the vehicle after an emergentransport, the TPMS still read 41. Max 51 psi on the tire.
At Co$tco two days earlier I had set their tire inflator at 45 psi.

Are you willing to bet your life on that?

Tires flex with EVERY rotation. Flex builds heat. Measure your pressure after a blood run. Take the tread temperature with an IR temp gun. Data, not supposition, informs. Anything else is a guess.


The TPMS read 41 psi about 10 minutes after returning from themergency delivery.
On hot days I often feel the left rear tire on the way to the hatch. Not very hot but I am not calibrated.

IR gun would be nice! The TPMShould be a good indicator.

Given your high speed use and the manual’s recommendation, I’d use 0W-20. But make sure it meets ISLAC GF-6A plus API SP standards, not all 0W-20 does. It’ll say that on the back.


Assume Mobil1’s “Hybrid” oil would meethat.
(Blood call.)

It looks like it does, I checked. Don’t assume, though, not all Mobil1 0W-20 oils do meet the spec.

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Thank you.
Massive hemorrhage.
RX350h easily attained 125 mph on vacant stretch of Interstate.
Cooler tires. TPMS all 39 psi.

The owners manual states for high speed driving to “add 8 psi”.

Standard pressure 33 psi plus 8 psi = 41 psi cold.

Thank you.

Years ago Montana had no limit in some stretches of I-90. My friend from Helena said she often drove 100 mph and was passed!

I thought “Standard” pressure was 35 psi.
While driving iheat, the tires have not attained 51 psi - Max on the tire sidewall.
Seems that heat has moreffecthan speed if well inflated tires.

I want to point out that the 16 on 0w16 is NOT the viscosity of the oil when hot. It is the grade of the oil regardless of temperature, or as the owners manual calls it “viscosity characteristics”. 16 grade oil will have a viscosity curve of viscosity vs temperature. 0w16 grade oil will have a slightly different curve, it will be flatter so it thins out less at higher temperatures than a straight grade 16 would. It is also thinner at lower temperatures than the straight grade 16.

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