IMHO 15w-50 is initially too heavy at start up for proper lubrication. The ultimate ambient temp effects start up lubrication more than it does a fully warmed up motor. If it's hot outside the 15w should be sufficient to provide flow and lubrication, if it's -40 probably not. 0w- or 5w- lubes better at start up at any ambient temp. As long as you have pressure of appx 10lbs per 1000rpm you have sufficient pressure. Pressure in and of itself is not an indicator of good lubrication. The lighter oil may well find leaks a heavier oil doesn't but then those leaks should be repaired and not masked. Lubrication provides a surface preventing metal to metal contact, this is provided by flow not pressure. Pressure is resistance to flow. Obviously this is a complicated and sometimes heated subject but I personally would go w/the 0 or 5w- oil. I use Mobil 1 5W-30 here in Houston.

Eric
84 Z-51 Auto

 

Correct me if I'm wrong but as far as I remember. The vicosity of the oil is only the first number. The second number is the shere strenth. A 10w30 stays 10 weight. but at a certain temperature determined by its designers it's molicules bind together to give the shere stenth of a 30weight. A few years back Cycle World had a great article on oils and how they work. If I can find it I'll pass along any info I can.

just my 1 cent worth.

 

SOUNDS GOOD ,HOPE YOU FIND THE ARTICLE I WOULD LOVE TO NO THE TRUTH[8D]

 

The first part of the viscosity designation (W grade) is an indication of the oils ability to help an engine crank and start and for the engine to pump the lubricant. The lower the viscosity, 0W is the lowest, the lower the temperature that the product can be used at. The second part of the viscosity grade is the viscosity your engine sees at normal operating temperature. It is not safe to assume that a higher viscosity grade is always better for your engine because of factors such as engine design, internal clearances, fuel economy requirements, etc. Always consult your Owners Manual when selecting oil for an engine that has not been modified.

 

Okay, I don't want to get into a flame war on this or anything but this one is too much to pass up. Killer is harassing CK for using the wrong spelling (a homonym) of a word, and then he misspells ridiculous in his signature. Was that on purpose? I notice the word "cuz" and assumed that it is slang for "because". But is "rediculous" slang for "ridiculous"?

 

Snap!!

Killa ur bout a year & half late on thes 1.

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