Thread: 30w oil
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Old 02-09-2019, 09:53 PM   #18
30 Closed Cab PU
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Join Date: Aug 2018
Location: Wisconsin
Posts: 1,515
Default Re: 30w oil

Originally Posted by Werner View Post
Good evening!

These motors are unsuitable for low viscosity oils. The large installation tolerances require a thick liquid oil to maintain a hydrodynamic lubricating film in the crankshaft bearings.
In addition, a low-viscosity oil leads to increased oil consumption and the combustion residues in the combustion chamber got too much.
My understanding of multi viscosity oil.

10W40 - has the viscosity of a straight 40 weight oil at higher/operating temperatures. Straight 40 weight oil when at low temps is much thicker viscosity, so does not flow/lubricate well.

Multi viscosity oil changes so it has the viscosity of a straight 10 weight oil at very cold temperatures, it is not the viscosity of a 10 weight oil at high temperatures which would be very thin.

So a 10w40 oil attempts to keep the same viscosity for both temperature extremes.
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