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Old 03-29-2014, 02:50 AM
dan512 dan512 is offline
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Quote:
Originally Posted by bobcowan View Post
That is definitely a bad idea.

During start up, a thick oil like 15W or 20W will not lube your engine very well. You've probably heard that the majority of engine wear occurs at start up; and that is generally true. Thicker oil when cold will make that worse.

Viscosity of oil is measured at a standard temperature. a 5W oil will pour like 5 weight oil that's been chilled below 0*. So buy a quart of 20W-50 oil, and put it in the freezer. In the morning, try and pour it out.

Thicker oils when hot do not provide any additional benefit in longevity or performance. The do require more energy to move around, and put more strain on components like oil pump drive shafts and distributor gears. You've heard of people shearing the gear pin, and this is how it happens.

You need a thick enough oil to maintain proper oil pressure in all conditions. Anything more is a waste of energy. Start with a 5W-30 and see what you get. If you're dead set on a heavy oil, use a 5W-40 or 0W-40.
I read you Bob, makes sense too, but then why does Ford recommend 20W50 an why do so many engine builders recommend heavier stuff also?

Not an easy topic I'm tackling here
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