0W 30 over 0W 40 – brief road trips?

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Gorrillaas
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Hey everyone!

historical background


Chevrolet Corvette M276 with 55,000 miles on the odometer. Always wait for the revs to settle and the oils to rise to temperature before giving it beans at start up; this is why I tend to make shorter journeys.

Would a thinner 0W 30 MB certified hose be preferable than the thicker 40 hose, given the shorter trips? This would allow the oil to circulate more quickly, causing the parts to heat up more rapidly.

If not, how about 0W 40?

Best regards
MBcarOWNER
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Select the specified and suggested range of viscosity 👍.
Gorrillaas
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They clearly state 0W40, however it is MB rated.

Staying with that is my plan.
RuthHimmic
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At startup, the zero is what matters.
Do any of you recall 20w50 multigrade?
RogerSalesCar
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The 0W40 should circulate just as quickly as the 0w30 because oil pumps are basically positive displacement devices; the only difference is the pressure required to accomplish that circulation.

Oil is heated by what?


Heat from the engine and oil-related frictional losses in the bearings caused by the viscosity of the fluid.

Thicker oil has greater frictional losses in the bearings and, as a result, is heated to a higher temperature than thinner oil. Therefore, contrary to your expectations, the answer is likely to be negative.

Since they are both 0W oils, my decision to use the 0W30 for simpler winter starting was based on the assumption that the car would sleep when driving. However, I should note that this is only a marginal benefit. Opt for the OW40 for enhanced protection if the vehicle is kept in a garage and, in particular For engines like the M271, which have a questionable timing chain design.
MercedesMan98
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I still use it on a few of my older vehicles, and my M119 uses 15W50 synthetic.
shamaspoor
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It would be helpful to hear the thoughts of a neutral mb expert on the MG Redline additive. Does this product come from an oil snake? If not, then what is it? How does it work? What effect does it have on the oil? Is it safe?
MercedesMan98
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No dealer worth their salt would suggest an addition, in my opinion. Spend your money wisely and change the oil every five thousand miles. Many additives are used in modern oil.
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